Chiming in for the first time to say that the macbook/pro software update is supposed to fix an issue where the keyboard and/or the trackpad of macbooks with Leopard on them would freeze up and stop responding for various lengths of time.
As I recently had my first brush with that problem a couple weeks ago, I hope installing that update will have fixed things, but since I haven't had a resurgence of that problem since the first time it happens, it could have fixed things just fine for all I know. I've also heard of other people still having keyboard issues, but since the person I heard from about that said it might be a hardware issue, there's no way to tell if it's the same exact problem afflicting everyone who's had it.