Going off Apple's latest 10Q filing with the SEC, it appears they sold 28% more total Macs than they did the same quarter in the previous year. Desktop sales were about the same, but the notebooks took off amazingly, a 65% increase in sales. And to top it off, this latest quarter was a week (7%) shorter than the previous one, so we can probably say sales rose almost 30%, adjusted.
Overall PC sales growth for 2006 was 10%. Apple's was 28% (unadjusted). That is a huge relative growth.
If PC users had been switching at the rate of "9000" per day, that would make 3.24 million switchers per year
Current sales total to 6.4 million per year. 3.2 million requires only half of those be switchers. The PC market is HUGE, 240 million shipped last year, so a million more from one company doesn't count for much in the percentages. But it is awesome for Apple shareholders.