Who knows. I never really trust stats from them or Websidestory.
Still leaves Apple with an estimated 2.8% share worldwide, even using your own figures. That's not much is it, after over 30 years in business by Apple.
Considering that Apple hit rock-bottom in the 90s, it appears their climb back up is doing extremely well, with very impressive growth. Two things, a switch to OS X (leaving the legacy behind, as opposed to Vista) and then to Intel have been instrumental in their recovery.
Not to mention the inevitable slowdown in Windows PC sales in the run up to Vista, something that the February and march figures will rectify.
Ballmer doesn't think so. People see basically flat growth for the general PC market for a while. Meanwhile, Apple continues very good growth far beyond the industry average.