Thanks for all the input everyone. Given that the price difference is close to $1000 between a new MBP and an old one, we're getting another Classic that has applecare. In the end, I think both machines are superb computers!
hopefully you haven't done that yet... notice how everyone who recommends the classic clearly over the unibody doesn't actually own a unibody.
i've had both. classic for over a year (september 2007 until october 2008), and since then i've had my unibody, and i HIGHLY recommend the unibody.
1. no 8600m GT issue (that's why i switched to the new design... my logic board had to be replaced twice, and then the third time the graphics didn't fail but i was experiencing regular kernel panics)
2. trackpad (really changes your computing style. it cannot be explained in words how intuitive it is to use after a month of acclimation.)
3. construction (contrary to what a few have said here, i am a college student who travels with his MBP almost daily and let me tell you, the uMBP is FAR sturdier than the classic. i had both!! it's better made in almost every way. think about it... why would apple - or anyone else, for that matter - take a step back in design/construction? remember that whole "brick" saga before we knew what it was going to be? remember all the excitement of that construction process? it really worked!!)
4. lifespan (since undergoind this redesign, it will be 5+ years until the exterior of apple's notebooks change again. do you really want the design that debuted in 2003, with the powerbook?)
5. capability (has far newer chipset, better CPU, supports more RAM, better battery life in 9400m mode, better video performance in 9600m GT mode)
6. connectivity (you may not have one now, but the new apple displays use miniDP and the classic MBP does not have that port... new one does, and monoprice sells cheap adapters)
so even if you listen to the haters saying the old ones are better made (they're not), balance that against the features and capability of the new one. with all else being equal (it's not), why buy the older design?
and since it's not really equal at all, i'd say it's an easy choice - get the unibody. i've had both, and i couldn't be happier with the uMBP.