Not sure if this is widely known about but I've spoke to a few colleagues who's Apple Care start date (or original purchase date) as been incorrect.
I'm waiting for my MPB to arrive and got an email regarding my Apple Care the day after I saw my first shipping notification. The Apple Care email advised my cover would start 15th June 2007 and expire 15th June 2010.
I emailed my sales contact at Apple who bounced my to aftersales (I didn't expect much more TBH), so called to find out where my order was, and whilst on the phone asked them to hold off starting my AppleCare until they'd delivered the machine.
After only a little bit of dispute and being put on hold, she came back and asked that I call AppleCare direct when the machine arrived and they'd reset the start date. So this differs a little from what I've read elsewhere, but it does concern me that they appear to routinely start the cover early; this is for a machine that's still in Apple custody somewhere between goods-in and China!
Either way I have every intention of getting the start date correct, cause there's no way they'll be listening so hard on June 16th 2010.