Apple can come back with an ad where they get that same exact laptop from best buy, get it's vista experience rating number, then install vista on a macbook pro 17" and get it's Vista experience rating. Im willing to bet it would be much higher than that laptop from best buy, maybe even if they installed it in a virtual machine without even running bootcamp it might get a better score. Then show how long the battery lasts on the two.
Point: sure you can get a cheaper laptop running windows, but the mac that you didnt buy because it was 'too expensive' is loads better than that PC you just bought. Sony marks their prices up, so I'm sure if you got a 17" from them, it'd be the same amount as a macbook pro and im still not convinced it'd get the same vista rating as the mac would.
Apple isnt going to make crap. My two year old MBP 2.2 ghz is just as fast as it was when i got it, not running slow because of malware or having to run a virus scanner every time it boots (which it does in about 30 seconds). On the other hand, even just my XP virtual machine is dogging after a year of having it installed..on a virtual machine that all i have on it is office 2003 and some software for my job! I used PCs up until 4 years ago, and every one I've had was full of crap after I bought it! dell or HP or Gateway, they all would fill it up with trial programs of this and that. You try to uninstall them but it is to no avail. Then you have to put virus protection on it, which decides to run at the most inconvenient times, slowing down the entire computer. My family gave away all of our PCs after moving completely to macs. They werent even worth selling, and a couple were a year or two old.