Gruber makes some pretty sane predictions, and they’re probably well-sourced:
More RAM will significantly help performance, too, and I believe the new iPhones will sport 256 MB of memory, up from the 128 MB in all current models. Prices will stay the same — $199 and $299 — but storage will increase to 16 and 32 GB. The improved performance will be one of the major new features that Apple will tout, but the only tech specs Apple will publish will be the storage capacities — just as with previous iPhones and iPod Touches Apple won’t publish any specific technical information regarding RAM or the CPU. (The CPU in particular, I believe, is something Apple regards as secret sauce.)
Looking forward to this one. More RAM and CPU would make for a much better iPhone, and I still love my first-gen.