We don't get iPhone game sales figures with our NPD numbers. Thankfully, we do get them with our periodic comScore App Store sales numbers!
The market research firm have released a list of the top 25-selling iPhone apps (well...the 25 most-downloaded, since free apps are included) since the handset store launched last year, and of that 25, 12 are games, including #1. Which is Tap Tap Revenge. Amazingly, comScore reckon the game has been downloaded by 32% of iPhone owners, which is one hell of an attach rate.
Other games scoring highly on the sales charts are Touch Hockey, Pac-Man, iBowl and Labyrinth, though sadly, there's no room for either of our faves, SimCity or Space Deadbeef.