You may be interested in this article by John Carmack, the brains behind the infamous “Doom” video game of the 90s.

He spends some time talking about some iPhone projects that he is interested in.

Check out the article here:
http://www.idsoftware.com/wolfenstein3dclassic/wolfdevelopment.htm

There are some interesting perspectives on programming problems that you may encounter when writing game code for the iPhone. It is a bit advanced perhaps, but is pretty neat to see how a luminary deals with some of the unique problems of the platform.