Welcome to the 43rd installment of The Wal-Mart Weekly, a column dedicated to bringing you insight, wit, facts, results, opinions and just a bit of everything else when it comes down to a very hot topic these days: Wal-Mart.

Last week, I looked at Wal-Mart Stores, Inc. (NYSE: WMT)'s 2007 in review and summed up all the retailing giant had going for it last year along with all the negatives against the company as well. Wal-Mart did a lot of things right in 2007, but still had to fend off daily attacks from its enemies and just about any other entity who took shots at the largest target in the world.

Apple, Inc. (Nasdaq: AAPL) and Amazon.com, Inc. (Nasdaq: AMZN) have been hot companies and, yes, hot stocks. But the two companies are taking shots at each other.

Of course, as was expected, Amazon.com launched its digital music store, which has about 2.3 million songs. But as the company is wont to do, it has engaged in some price cutting. For example, a song costs between 89 cents to 99 cents. An album goes for $5.99 to $9.99.

Well, to get some analysis on this, I turned to Rafi Mohammed, who is an expert on pricing. He operates Pricing for Profit and is also the author of the book, the Art of Pricing. According to him:

"Amazon's entry into the digital music market will significantly affect Apple. Drawn by steep discounts, many music aficionados will switch to Amazon's service. This will inject some much needed competition into the digital music market, which will help music companies gain negotiating power. Additionally, a strong iTunes competitor may offer co-branding opportunities for music device makers. My prediction: this is the catalyst to music companies moving to their beloved variable pricing (some prices higher than others) model and new digital music players that will successfully challenge Apple's iPod."

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 DealProfiles.com.

The Wall Street Journal's Lee Gomes makes an interesting argument [subscription required] about digital music that iPod and iPhone buyers should consider: "[B]ecause both compressed music and the iPod's relatively low-quality earbuds have many limitations, music producers fret that they are engineering music to a technical lowest common denominator. The result, many say, is music that is loud but harsh and flat, and thus not enjoyable for long periods of time."

According to one expert, high frequencies which sound good on a CD may sound poor on an MP3. Music today is also being released at higher volume levels, which can also weaken the distinctions between high notes and low ones in a track.

So add that to the list of complaints about Apple Inc. (NASDAQ: AAPL). MP3 and iPods are weakening the quality of recorded music. Part of the problem is the ear buds that are commonly used with iPods are relatively poor quality.

But hopefully engineers are hard at work making MP3 technology better, just as they did with CDs when they first came out. Either way, don't count on CDs making a comeback any time soon.

The New York Times [registration required] reports that Dave Stolte took his Apple Inc. (NASDAQ: AAPL) iPhone to Ireland and England in July and returned home to a little surprise -- a bill for $3,000.

Stolte's $3,000 phone bill was a result of unanticipated European roaming charges. Consider the case of mortgage consultant, Neil Dingman. Dingman used his iPhone only a few times on a European trip this summer and had expected to see just a small increase in his next bill for roaming charges. But he failed to turn off an iPhone feature that automatically checks e-mail. Thus his iPhone roamed over networks in Italy, Croatia and Malta more than 500 times. And he ended up with $852.31 in roaming charges.

But Stolte's story has a happy ending. Thanks to the posting of Stolte's bill on the Internet, AT&T Inc. (NYSE: T) went from giving him a $100 credit to full credit for that $3,000 iPhone bill. The lessons? Turn off the e-mail checking feature if you're out of the U.S. And if you get a ginormous iPhone bill -- post a complaint video on Google Inc.'s (NASDAQ: GOOG) YouTube.

Peter Cohan is President of Peter S. Cohan & Associates. He also teaches management at Babson College and edits The Cohan Letter. He has no financial interest in the stocks mentioned.

As I was following Apple. Inc.'s (NASDAQ: AAPL) "The beat goes on" event yesterday, I caught myself wondering this: can Apple roll out incremental features to its iPod line and get the market excited once again? I'm not sure that happened, as Apple shares remained stagnant during the event and then closed down almost nine points. This on a day when the company refreshed its entire iPod lineup with new "models." Ehh.

Did Apple just suffer along with many other tech stocks in yesterday's downtick, or was it something more? Apple CEO Steve Jobs has a wonderful way of making the world think each 'new' Apple product is somehow a first or one-of-a-kind, but most aren't any longer when it comes to the iPod line (save the iPhone, which is easily a revolutionary product).

Basically, Jobs trotted out the same products -- from the iPod Classic to the iPod Nano to the iPod Touch -- with incremental feature upgrades and more marketing glitz than a glazed donut. The market seemed unimpressed, all things considered. But, there's more.