Hey Einstein -
Smarten up. It's impossible for severe economic conditions to not impact sales of Macs. But your interpretation of the marketshare data is a distortion.
In hard times Mac users are not going consider buying a PC because it's cheaper… don't you get it!… isn't EVER going to happen. If the money's not there and borrowing doesn't make sense, they'll just get by with the Mac they have until their personal financial situation changes for the better.
As for would be Windows switchers… well price always matters because there's no significant distinction between one POS PC and another… it all comes back to running Windows no matter what.
So there will likely be fewer switchers, but when the pain & hassle of living on Windows gets to be too much, still some of these folks will step up to the Mac.