Well, it's definitely the game. Booted it up after letting it get cold, Uncharted crashes in the cave again. I think it's to do with the auto save, since every time I reload my game, it loads exactly where it crashed. Played COD for over an hour afterwards and it never froze (still playing it now).
Just a heads-up about the whole Uncharted crashing thing, I've got a feeling it's related to the new firmware, not the new slim model. I've heard about it from folks on the official PlayStation forums, some also said that they've heard about it on other sites too. I've had Uncharted ever since I first got my PS3 and finished it several times and it has never crashed on me. I'm gonna try playing it later on my 40GB and see what happens.
Yeah it'd be sweet if you could get back to us on that.