Lo and behold- we were just talking about Painkiller and here's an iOS version of the game! Painkiller Purgatory just hit the platform today in lite(demo), standard, and HD (for the iPad) editions.
The title promises fast, "visceral" gameplay with "high octane" weapons and the series' "trademark giant boss battles". Painkiller is one of our favorites and is a criminally underrated franchise- the first iOS entry looks great but we have yet to play it, so commenting on the controls can't be done quite yet.
Once we dig our clawn into it, we'll have a review up.