Many investors know about the key metrics that provide clues about the U.S. economy's health, and where it's likely to head in the near term. Retail sales, housing starts, UPS (NYSE: UPS) and Fed Ex (NYSE: FDX) deliveries and, of course, those infamous corrugated box orders, all provide clues about demand at the retail and wholesale levels, and are positively correlated with increases in U.S. GDP.

What's another metric worth monitoring? Office rents -- and here, like the recent statistics reported for the above metrics, the numbers are not good.

Office rent charges per square foot in Midtown Manhattan, London's West End, and Central Tokyo fell in Q3 for the first time since 2002, a report from CB Richard Ellis indicated Tuesday (pdf).

In New York, Midtown Manhattan office rents fell 2.7% to $98.08 per square foot. Midtown Manhattan includes the headquarters of many of the world's multinational corporations and the Broadway theater district, but does not include the Wall Street financial district, which is located in Lower Manhattan.

In London's West End, occupancy costs declined 5.1% to $248.66 per square foot. In Central Tokyo, costs dropped 5.3% to $184.26 per square foot.

Economist Richard Felson told BloggingStocks Tuesday the fact that rents are declining the world's top three financial centers for the time since 2002 is not a good sign. "It's further evidence of the spread of the recession," Felson said. "Very rarely do you see rates in all three cities declining at the same time. Then again, very rarely do you see all three regional economies in recession at the same time, either, which shows you the fix we're in."

The Times of London reports that Lakshmi Mittal, an Indian steel magnate, is purchasing a $230 million London home from U.S. hedge fund manager, Noam Gottesman.

Mittal is Britain's richest man who is spending about $16,000 a square foot for the detached residence on Palace Green, an extension of Kensington Palace Gardens, where several billionaires have their London homes. The $230 million price is 40% more than the previous record of $160 million for property in London's nearby Upper Phillimore Gardens.

Gottesman is fairly well off. His net worth has been estimated at $920 million. But if this sale goes through, he will be a billionaire.

Peter Cohan is President of Peter S. Cohan & Associates. He also teaches management at Babson College and edits The Cohan Letter.

When it comes to mergers and acquisitions (M&A), there has been little doubt that New York City is the center of the action. However, with the credit squeeze -- as well as the emergence of developing countries, such as India and China -- things are changing.

Take Deutsche Bank AG. This week, the firm announced the co-heads for its M&A group, Henrik Aslaksen and Brett Olsher. And they will operate out of London, according to a report from the Wall Street Journal [a paid publication].

Consider something else: the heads of M&A at Goldman Sachs (NYSE: GS) and Morgan Stanley (NYSE: MS) are also based in London.

There's definitely logic to this. After all, corporate clients want a global perspective and capability. And, for the most part, London has had a storied history in finance -- with strong ties to the rest Europe, the Middle East, and Asia.

As for Olsher and Aslaksen, they both have extensive global experience -- working on such high-profile deals as Tata Steel's purchase of Corus Group.

Tom Taulli is the author of various books, including The Complete M&A Handbook and The Edgar Online Guide to Decoding Financial Statements. He also operates MergerBook.com.

Almost on cue, the European Central Bank took a page out of U.S. Federal Reserve's playbook Wednesday.

In a widely-expected statement, ECB President Jean-Claude Trichet warned that the euro-zone's inflation surge was likely to last longer than expected, Bloomberg News reported Wednesday.

The comments came one day after the ECB made $500 billion in short-term loans available to banks to avert a year-end liquidity crunch. The $500 billion move was part of a coordinated effort among the world's major central banks to increase liquidity in the international finance system to head-off a potential credit crunch stemming from subprime mortgage and related asset defaults. Many economists and analysts expect the major central banks -- the ECB, the Fed, the Bank of England, the Swiss National Bank and the Bank of Canada -- to continue to sequentially add liquidity to the system through at least Q1 2008, and probably longer.

On Wednesday, Trichet said the euro-zone "faces a 'more protracted' period of elevated inflation than previously expected, indicating no imminent plan to reduce interest rates."

During the market disruptions of the past couple of months, we saw Apple (NASDAQ: AAPL) fall from a high of $148 to a low of $118 ( man, what an opportunity that was!!). The stock is now back up to $141 and this may be your last chance to buy it here under $150. Why? A lot of catalysts are on the near term horizon.

Apple finishes its fiscal year in 11 days. The September 30 quarter and year-end will wrap up an exceptional year for Apple, yet many would argue that the best is yet to come. I expect the year finishing in 11 days to have final revenue numbers of $24 billion with earnings per share coming in at $3.75. iPhone revenues will be somewhat relevant, but that piece of the Apple story is JUST BEGINNING. As Apple exits fiscal year 2007, the more relevant story is still the overwhelming success of the iPod with the corresponding iTunes store, and of course, the newly revamped Mac computer. Mac is gaining market share in a fairly fluid market.

The iPhone production is ramping up. For the year (calendar year), Apple had planned to produce 3.6 million iPhone units. That number is now at 4.8 million units in planned production. European nations will be rolled out for iPhone availability beginning in the calendar fourth quarter with the UK and Germany getting ready for the onslaught.

Last week on BloggingStocks, I wrote about Playboy Enterprises, Inc. (NYSE: PLA)'s foray into social networking, and wondered whether it would help the company to launch itself out of the doldrums.

Michael Schneider of www.barrelomoney.com left a comment to let me know that he thinks the company is already launching itself out of the doldrums:

Playboy, in our view has already started a substantial turnaround that has set the company of the right course. they have added many new sources of revenue and have strengthened the brand. Recent results are telling as many print media companies are floundering and competitors like New frontier turned in weak results.

But the stock isn't showing evidence of this turnaround -- which is good. If the company really is turning itself around, the stock could present an opportunity for investors.

Now we have the latest evidence of Playboy moving in a new direction: It's opening a store in London, establishing a presence that has been missing there for the past 25 years. Playboy is also looking at opening a casino in London.

There's been a lot of evidence lately that Playboy is at least trying to reinvent itself and become relevant again. If you think it has a chance, you may want to look at buying the stock.

When I worked in Chicago's Loop, I used to see the traders everywhere, with their brightly colored jackets and their enormous badges. Whether in their smoking circles, crowded into the restaurants and bars, or simply scurrying from one place to another, there was a air of frenetic energy about them, and though sometimes looking weary, they always seemed to be having a good time.

Well, as it turns out, Chicago, home of the championship Bulls and Bears, is also the top trading city in the world, according to a survey of traders by Trader Monthly. London, New York, Dubai, and Miami rounded out the top five.

The two largest U.S. futures marts and the largest U.S. options exchange can be found in the Windy City. Trading is "in the city's blood," said the magazine. Just this past week the Chicago Mercantile Exchange (NYSE: CME) had its second-highest volume trading day ever.

Trader Monthly rated cities on several factors, including trading infrastructure, taxes, access to capital, weather, nightlife, and time zone. Especially popular with traders was the real estate market; Chicago is infinitely more affordable than London or New York, the next two runners up.

Forbes.com traveled to the U.K. to see just how expensive the London real estate market has gotten. The answer? Expensive. In December, prices reached their highest in six years: $1200 per square foot, up from $650 in the year 2000. Flats, like the one seen in the video below (click the image) -- in spite of the particleboard cabinetry, sky blue carpeting and some wicked faux-limestone shower tile -- will run upwards of £1 million, or a cool $2 million.

This three-bedroom, three-bathroom flat in Mayfair -- a posh London neighborhood -- is 1000 square feet, boasts a view of Green Park, close proximity to the Piccadilly district and needs, in the words of the agent, "a bit of an overhaul."

So, why are the prices so high in this city, especially now that Cats is not longer running? Gary Hersham, Managing Director of Beauchamp Estates -- a London agency that handles "high-worth" individuals -- says that wealthy foreigners who love London are setting the tone. "It's like the stock market today," he says. " House prices are moving with the same rapidity as share prices moved."

B. Brandon Barker is the author of the novel Operation EMU.