Yesterday those willing to get fancy with forced firmware updates and such were able to sneak into the iPhone's App Store and buy games for the device early. Today, firmware 2.0 and access to those 30 or so games are official.
If you're looking to buy a game for your iPhone than make sure to check out our Ultimate Guide to iPhone Gaming which includes quick impressions of 20 or so of the games as well as screenshots, videos and details for most of the games currently available and a bunch yet to come.
Our most recent update to the guide includes impressions of Tetris, EA's Sudoku and Crash Bandicoot Nitro Racing. Personally, I've played around with 15 different iPhone games and my favorites so far include Super Monkey Ball, Bomberman Touch and Trism... oh Trism. Oh, I also really like Zen Pinball.