Either an entirely new control scheme for an FPS or a hell of a lot of tweaks is required for that. The "drag-select" mechanism shown in N.O.V.A for the iPad is a thought in the right direction but it's going to have to pervade the entire control scheme to really make it a slick experience.
Don't get me wrong I enjoyed N.O.V.A a lot but an FPS with those controls can never be triple A on the iPhone or iPad.
A city builder or dungeon crawler however.. those are AAA iPad titles waiting to happen, however due to the larger time investment required we have seen almost nothing so far.
PS I'm happy for you that you like city builders, dungeon crawlers and RTS games so much you have to remind us why their going to be so good on the ipad twice in this thread and at least once in another thread about shooters. Cool man! To me however, their just something to avoid while I look for good games Hopefully with that nice large touchscreen and a 1 gig processor we will have some really good FPS's coming up!
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