Personally, I like the way the screens are on the PowerBooks and iBooks, but that's just me. They seem sturdier than before. More solid.
Anyways, the current lineup of PowerBooks is a dream come true. You have an ultra-portable (not super thin like a tiny vaio, but small by terms of laptops) 12" PowerBook that you can get with a SuperDrive. It's fast enough to handle photoshop, final cut pro and express, and everything in between. The 15" PowerBook has just the right size screen (although I can't say much about the resolution, as I don't use one...), packs a punch with the 1.25ghz G4 and the Radeon mobility 9600. The backlit keyboard is really cool, and the actual keyboard on these things is much, much better than the TiBook or iBook keyboards. As for performance, the dropping of L3 cache doesn't seem to have any effect. I guess that in the past, it was something with the processor that actually needed the L3 cache, where here, the increase in L2 cache seems to do the trick. I also think that the aluminum finish is better than the TiBooks. The TiBooks were nice, but the aluminum PowerBooks seem more sturdy. I've dropped mine (12" PowerBook), and it didn't even dent the aluminum. As for heat, that's usually based on the comfort level of the user. I can tolerate quite a bit of heat, and it's actually pretty nice in this cold dorm room, but it should only get hot when you're running any CPU, graphics, or disk intensive apps, such as folding, photoshop renders, or disk things... You can't feel the heat through the keyboard (or at least I can't), and if you put it on a desk, and get one of those riser things, it makes a big difference, elevating the back of the PowerBook making it easier to type on, and raising the screen. It also keeps it cool.
If you need a laptop now, I'd say get the 15" PowerBook. New stuff will always be coming out, but sometimes you just have to bite the bullet and make a purchase. It'll be obsolete in about 8 months, but that's longer than most PC laptops. My 12" PowerBook, which is 9 months old, still works fine. I don't feel it's obsolete, just because I don't have DVI, USB2, or a 1ghz processor. Actually, when I got mine, I thought that the lack of L3 cache would make a big hit on performance, but my 12" PowerBook runs just fine.
I hope you make a decision that works best for you. I'll just warn you that even centrino laptops have problems, like being made out of plastic, and will become obsolete before your 15" PowerBook.
Good Luck!
