Microsoft Corporation (NASDAQ: MSFT), a company in the same competitive league as Apple, Inc. (NASDAQ: AAPL), Google, INc. (NASDAQ: GOOG), Yahoo! (NASDAQ: YHOO), and International Business Machines Corp. (NYSE: IBM), posted its Q4 earnings release after the bell on Thursday. As I was writing this paragraph, shares of the software giant were trading down over 6% in the after-hours session. Looks like the market was disappointed.

To be certain, the results weren't great (of course, no one was expecting them to recall the company's growth story of yesteryear, I'm confident about that, let me tell you). Sales were down 17%. Operating income on a dollar basis dropped 30%. And, on a reported basis, Microsoft's per-share profit, calculated out to be 34 cents, declined 26%. On an adjusted basis, adding back 4 cents for a few items, earnings came in at 38 cents per share. According to my earnings preview, that beat estimates by two pennies.

Dell (NASDAQ: DELL) seems to be positioning itself as the de facto corporate champion of saving XP and saving its customers from Microsoft's (NASDAQ: MSFT) much-maligned Vista operating system. Dell announced it would charge $20 to $50 extra to some customers to "downgrade" to Windows XP. Dell even puts the "downgrade" in quotes, the idea is so ridiculous. In reality the fee is more like $100-150 because many customers will have to upgrade their version of Vista to downgrade to XP.

On the surface, this extra charge may sound like bad news, that getting XP is going to be even more difficult. But I see this as a way for Dell to ensure there is still some legitimate way to keep getting XP even after June 30, when Microsoft wants to kill it off.

There's been much speculation about whether Microsoft would relent and postpone the demise of XP another time. I also take this news to mean that it will not. Time's up. In some ways the deadline was just moved up to June 18--that's when Dell stopped pre-installing XP.

A recent study by Evans Data Corporation shows that developers don't like Vista any more than the rest of us. Six times as many are clinging to XP than switching to Vista. Only 8% of developers are working on programs to run on Vista, compared with 50% who are writing for Windows XP. That's not good news for Microsoft (NASDAQ: MSFT), who hopes that its customers will grudgingly tolerate the withdrawal of XP on June 30.

Many are begging Microsoft to relent, especially InfoWorld. The developers do plan on doing more work for the troubled operating system next year, but still not as many as are hanging onto XP. Next year, 24% of developers expect to target Vista while 29% will still work with XP.

Evans data doesn't say how much the Vista disaster has helped Linux and Apple (NASDAQ: AAPL), but it's clear Vista has sent many fleeing. eWeek reported last week that Apple now has a 14% market share -- nearly four times what it had in 2005. Using data from NPD Group, eWeek points out that Apple sells two out of three computers in the $1,000 and above category. That's largely because Macs are still way, way more expensive than PCs. If Apple ever got around to offering a computer at a price the masses were willing to pay, Microsoft might be in trouble. Microsoft may not hear the complaints about its operating system, but it understands that people want to pay less for computers.

Apple (NASDAQ: AAPL)'s newest Macintosh operating system -- Leopard -- will officially go on sale October 26 (just under two weeks from today). Unlike Microsoft (NASDAQ: MSFT), Apple releases new operating systems every year to two years. By contrast, the time difference between the release of Microsoft's Windows XP and Windows Vista operating systems was over five years.

That being said, so Mac users flock to upgrade every time a new operating system comes out? Hard to say, but every Apple fan I know borders on zealot (this is not a bad thing), and they do indeed upgrade every time something new comes out. I sense in many cases this is nothing more than psychological pride over genuine utility addition, but I could be mistaken.

Will Leopard's release bode well for Apple's coffers, then? Sure, but the question of how much is still up for debate. Apple's iPod phenomenon -- and now, iPhone phenomenon -- has translated into a growing market share for Apple PCs, and this "halo effect" has been tracked and followed with journalistic vigor in every nook and cranny of the media and blogosphere. What more could yet another upgrade add to this honey pot?

Apple's shares are sitting at an all-time high at the moment due to the perfectly-timed release of new iPods in September, along with the growing market for the revolutionary (yet already outdated in many ways) iPhone. Adding new eye candy to Apple's PC market will do nothing but help bump the company's stock price to over $200 if holiday sell-through does well. Perhaps the iPod was just a means to get customers flocking to Apple's PC segment, since in the long term, the iPod's remarkable sales sustainability can't keep up the torrid pace it has in the past -- or can it? Regardless, the company wants customers buying new PCs to think "Mac" instead of "Windows," and a newer version that looks and feels better than the last will only help that effort.