By their numbers, the iOS platform has had an estimated 32,438 games that have been released, while the consoles examined account for an estimated 17,150 games. Those platforms are: NES, Master System, Genesis, SNES, PSX, N64, Saturn, Xbox, PS2, Gamecube, Xbox 360, PS3, Wii, XNA, Xbox Live Arcade, Gameboy, GBA, DS, and PSP.
TUAW is quick to admit that its numbers or not very scientific and come with a bucket-full of caveats: a lot of duplicate games due to lite/demo versions and a lower barrier of entry for releasing a game than on any other platform. On the other side, many console games are multiplatform as well, accounting for duplicates on the other side.
Left off the list, however, are PC games including Flash and web games and a few other platforms, which would probably help close that gap in a big way, if not eclipse iOS entirely. It would have been nice to see Android and other mobile games represented, as well.
Still, it's an interesting, albeit inaccurate look at the energy behind iOS development and the sheer amount of games that have been released for the platform since July 2008. I'd wager the percentage of high quality games is probably lowest on iOS, though.