In speaking with John Carmack about the recent acquisition of id Software by Zenimax, he talked a bit about his excitement for the iPhone as a gaming platform and that he's spoken to Todd Howard (executive producer at Bethesda Softworks) about opportunities there.
Carmack also mentioned that his pet project, "DOOM Classic" for the iPhone, is nearing completion, saying "I expect to finish DOOM Classic in the next couple weeks."
After the fantastic job id did on the port of "Wolfenstein 3D" to the iPhone, it's definitely something I eager to check out. Good to hear that it's definitely close to release.