well, after a few days with the new model, i have to say it is a much bigger improvement over the old design than i originally thought. The unibody is amazing. It feels SO much more solid than the previous aluminum case (which was already pretty robust), and the keyboard is SO much nicer. It also runs much, much cooler when being stressed. Even when i rip DVDs with handbrake, i can barely feel it get warmer on my lap.
My only complaints are these:
1) When the keyboard is backlit, I see more "bleed" from behind the keys than actually coming through the key label.
2)I really do not like the idea of a glossy screen on a notebook computer... been against the idea since the first manufacturer's started doing it. I have used the computer in a few locations in my house, and whenever i am in a room with a few windows, the glare is pretty bad. I can only imagine how bad it is outside.
3) This is a bit nitpicky, i admit... but the little corners here...
...are quite pointy, and can be annoying if you rub your palm, or catch a sleeve on them (like i have). I would have liked them to be rounded off a bit.
So, overall, i am ecstatic that i was allowed to upgrade... definitely well-worth the uh... trouble... i went through to get them to do it.