Sure! And to be even more accurate, having a touchscreen as your second display opens up a lot of interesting options.
The thing is, games are generally developed for base hardware configuration. NGC had a mess of 4-player games, but PS2 did not, because it wasn't necessary; very few people owned multitap. PS EyeToy is also generally not supported.
Kinect has a glut of s/w available for it, but I believe there was a lot of moneyhatting in addition to a successful PR push on developers.
This is kind of a different thing, because there are SO MANY iPad and iPhone users already out there... I am feeling unsteady predicting what developer support for this feature will be like, but am still feeling like most devs will implement throwaway crap like that map she used.