Well if you're developing on a Mac or a PC for a different platform, wouldn't it make sense to push it for Mac or PC? Instead of waiting for development hardware from Microsoft of Sony you've already got the hardware.
I'd think that would be especially true for development of iOS games...you're already writing in Obj-C for iOS...just put in the right hooks for OS X.
I think there's some real potential there in using iOS with Airplay to get stuff onto the bigger screen. The problem, of course, is that you don't have big analog buttons and sticks to help control. It works fine if you're looking at the screen (GTA Vice City plays real well) or if you don't have to look at the screen (Hot Pursuit) but if you've got to use your thumbs to control something on the TV then not so much.