It looks like the IBM T41p is exactly what I was looking for--great battery life and an ATI Radeon9600 (or very similar), except, ouch, $3499 for the base unit! Granted, you can't have everything, but that is some serious cash. That is right about in the price range of a well-equipped Athlon64 laptop, which would have acceptable but lower battery life (about 3 hrs) and a far faster and more versatile CPU.
I am growing more and more wary of Dell though. They have great business support, but everything I hear about their end user support is a horror story, and it took no less than 5 transfers to be able to cancel an order I had placed earlier. Additionally, while I have not used their i8600, the Latitude D600 that I am on now, as well as some of the 5xxx series of notebooks, seem pretty flimsy and have less-than-outstanding keyboards.
If anybody manages to acquire any of these laptops, please do post a review. Free beer for the first reviewer! (well, not really)