AirTran Holdings (NYSE: AAI) made another bid for Midwest Air Group (NYSE: MEH) today, pushing to total up to $445 million. The new cash-and-stock offer of $16.25 bid surpasses the $16-a-share cash offer made TPG Capital and Northwest Airlines (NYSE: NWA) on Sunday and is 50 cents higher than their previous last-ditch effort on Sunday, hours before the Midwest Board said it would pursue a rival bid.

This is the fourth time AirTran has raised its bid for Midwest since December. Despite AirTran receiving support from nearly 63% of Midwest shareholders, management refused to relinquish control to the Orlando-based discount airline. Midwest's Board said it would "take AirTran's revised offer under consideration."

While the Board deliberates, let's take a look at exactly what would happen to Midwest if they were to be acquired by either AirTran or TPG/Northwest:

• AirTran wants to rebrand the airline under its own name and integrate Midwest's operations into its broader network.

• Under the TPG offer, Midwest would maintain its brand name and its current management. Northwest, a company that has had nothing but problem after problem since it emerged from bankruptcy earlier this year, would not participate in the management or have any direct control over Midwest. Instead, Northwest hopes to explore cost reduction strategies like joint fuel purchasing.

AirTran President Bob Fornaro said the Midwest Board is required to not only consider the price of a takeover offer but also the effect on employees and the community, according to USA Today. But what about the shareholders? A total of 63% of Midwest shareholders were willing to side with AirTran after a $15.75 offer, and now the offer has been improved to $16.25. It seems pretty clear who the shareholders want to be with.

Defining periods of irrational exuberance can be difficult. However, one method to do so might simply be to look at the headlines. Here are this morning's:

• Crescent Real Estate Equities to be purchased by Morgan Stanley (NYSE: MS) Real Estate
• Payless ShoeSource (NYSE: PSS) to acquire Stride Rite (NYSE: SRR)
  
• Dow Jones & Co. (NYSE: DJ) controlling shareholders, the Bancroft family, meeting to review News Corp (NYSE: NWS) offer
• Sallie Mae making management changes for its take-private transaction
• Alcan Inc. (NYSE: AL) rejects Alcoa Inc.'s (NYSE: AA) $27 billion offer as inadequate
• MGM Mirage (NYSE: MGM) approach by Kirk Kerkorian's Tracinda Corp requires delicate strategy.

The headlines are not too different from the 1980's LBO boom when virtually every headline was associated with a hostile buyout of some sort. Are we approaching the end of the buyout binge? Most likely not. These periods can last for years.

This buyout boom has been fueled by a number of factors. The most important factor has been undervalued stocks, which, in many cases, still remains. In the post tech-telecom bubble of the 1990s, investors went into a cocoon while U.S. company management continued to grow earnings and increase returns on investment.

What will end this buyout boom? My bet is a massive bull market which pushes valuations off the radar screen of private equity.

It was the news as soon as I logged into my computer this morning from my West Coast office: Rupert Murdoch's News Corp. (NYSE: NWS) had made a whopping $5 billion bid for Dow Jones & Co. (NYSE: DJ). The bid was unsolicited and, it seems, entirely hostile to the Bancroft family, who controls Dow Jones and seems to be rejecting the generous offer.

It's a cute story, very Guys & Dolls. On one hand we have Dow Jones with its flagship brand, the Wall Street Journal. The paper is everything about wealth -- its very emblem the center of all the world's markets, Wall Street -- the editors are known for their conservative bent, the writers are known for their unparalleled and brainy research, even the design is known for its long-time avoidance of peripherals like color printing and photographs. On the other hand, we have Rupert Murdoch and his gang of vagabonds, from FOX broadcasting (need I really say more than "Next on FOX... Are You Smarter Than a Fifth Grader?") to the vast spoiled brat of recent acquisition MySpace. They're very other-side-of-the-tracks, the kind of news organization that would get a tattoo on its buttocks and then try to slip it in as the senior picture in the high school yearbook.

They're not a match made in heaven. They're a match made for Joe Millionaire, or Broadway. It's not real life; it wouldn't work. Whether or not the money is right, the styles are so vastly different, the respective organizations' reputations so opposite, any so-called "synergy" would be lost before the first page of the merger agreement was drafted.