I've used my Powerbook with both a Olevia 32" LCD and a large RCA rear projector, and DVI has worked perfectly. The powerbook isn't beefy enough to upscale video to 1080i though.

I spent quite a bit of time working getting linux to work on the Olevia's VGA port, and found that the tv simply reported the wrong settings back to the computer. This tended it cause it to default back to 640x480, or something similar. If by chance you're using a 720p(ish) LCD, let me know and I'll try and find you the right modeline to try. (I think the modeline can be converted to the windows and mac custom monitor programs)

One thing of note is the 720p panels aren't really 720p, and if you want to drive them over VGA at least you need to feed them a resolution slightly wider than their actual dimensions. Overscan on a LCD. I guess old habits die hard.

Matthew