One of the things I find disconcerting is how creaky and flexy the plastics are on my 400MHz Pismo. The screen alone has 1/2" of free play in the hinge. My IBM Thinkpad T20, which is of a similar vintage as the Pismo is built like a tank. You can lift it up by one corner and it doesn't feel like it's flexing at all. Solid.
So, how are those new 15" PowerBooks? I think my Pismo 400 is long in the tooth and maybe ready to be retired. Flexy or solid?