While I'm not saying the TR8 is anything good or bad, I don't think the Crossfire will ever be a real valuable collectible. The car has one distinct disadvantage as far as collectibility goes: it's mixed heritage.
The folks that collect Chryslers won't want it, because of it's primarily Daimler heritage. And the Mercedes collectors won't want it primarily because of it's Chrysler name.
I think that is going to leave this car in the bargain bin for a long time. Which, by the way, is OK by me, since I'm hoping ot pick up a low mile SRT-6 in about 6 to 8 years, and I don't want to pay a bundle for it!