North - not many people are buying the 360 either, though more are than the PS3 right now. The 360 also had supply constraints for awhile I believe, while the PS3 is in plentiful supply, but I digress. As long as the PS3 is $600, its sales will be sluggish even if it gets some great games. Majority of people will wait for price drops (myself included) and at that high a price everyone knows it'll have to come down sooner rather than later. I'm not saying it won't sell, but it isn't going to sell well or really take off until that price drops a ton and/or it gets a massive library rolling. It'll still have a decent Xmas and might out-track the 360's holiday sales last year (especially worldwide).
And stop saying the PS2 started slow, it didn't, it had some supply problems initially but it sold like a rocket right out of the gate (~25M after its first full year, think PS3 will hit that end of this year? heck even Wii doesn't have a prayer), it's the PS1 that started slow and then mostly 'cause it was a new brand.