Two research and analysis firms have come out with figures for the PC market at the end of last year, and both show that Apple enjoyed dramatic growth year-over-year. Why, then, will you read about how badly Apple did?Both IDC and Gartner have released their figures for PC sales, both in the U.S. and worldwide, for the last quarter of 2009. Both show that the PC market "exploded" (IDC's word) and tout "the recovery of the PC market on a global level" (Gartner). Gartner has the U.S. market up 26.5 percent over the fourth quarter of 2008, while IDC came up with 24.0 percent for the same comparison. Worldwide, Gartner sees a 22.1 percent increase last quarter over a year ago; IDC sees 15.2 percent. Comparing the year as a whole, Gartner came up with 5.2 percent more computers being sold worldwide in 2009 than in 2008; IDC has 6.5 percent for the same figure.

And Apple didn't miss out on the party. In the U.S., it sold 8.2 percent more computers last year than in 2008 and enjoyed 31 percent 4Q-over-4Q growth, according to IDC; Gartner showed 23.3 percent for that latter figure. Both show an increase in U.S. market share of some fraction of a percentage. Continued growth: not bad, eh?

So why are so many observers covering this as a setback for Apple? It's because the growth in Apple sales lagged behind the average or behind other vendors. Gartner's 23.3 percent figure for Apple is lower than the industry's 26.5 percent; in IDC's figures, Apple exceeded the industry average but didn't do nearly as well as HP or Toshiba. Both firms now have Apple in the number five slot in U.S. PC shipments, behind (in order) HP, Dell, Acer, and Toshiba.

The reasons for this seem fairly obvious. For one, much of the growth at the end of last year was driven by the popularity of netbooks, and it shouldn't come as news that Apple still doesn't make one. "Low-cost notebooks and mininotebooks were the biggest contributors to the successful fourth quarter," according to IDC research manager David Daoud. Gartner analyst Mikako Kitagawa agrees: "Shipment growth was largely driven by low-priced consumer mobile PCs, both in regular notebooks and mini-notebooks. As economic weakness continued, buyers became extremely price sensitive. Low-priced PCs were good enough for many average consumers."

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Well, Mac customers have never really been looking for a "good enough" computer. Apple executives have made it clear the company isn't interested in making a low-price, low-margin, low-quality computer just to occupy a particular market niche. That niche exploded last year, but it remains to be seen what kind of legs the netbook market has. SquareTrade, a third-party computer warranty vendor, did a study last month of failure rates for laptops and netbooks that they'd provided warranty coverage for. They found that 4.7 percent of covered laptops experienced a malfunction in the first year, 20.4 percent in the first three years. But for netbooks, those numbers are 5.8 percent and a projected 25 percent. A one-quarter failure rate in three years -- that's the kind of experience that can take the wind out of a market bubble, if I may mix my metaphors.

The headlines may spin this as a problem for Apple, but look a little deeper. Besides the netbook effect, there's also the fact that Windows 7 came out during the last quarter, which, according to both research firms, at least provided a marketing boost for non-Apple PCs. It will be interesting to see if Windows 7 acts like a "delayed accelerant" to Mac sales, as a Broadpoint.AmTech analysis suggests Windows releases have in the past. If it does, look for another set of headlines in three months about Apple being "back on track." Of course, by then the iSlate will be announced, people will be jumping on the tablet bandwagon, and netbooks will be soooo 2009. Right?