I think a multi-play controller in general is a good idea, except I think they should just make it so all controllers work with everything. As for one I think it's retarded how despite the xbox controller & ps3 controller both having x, circle, triangle, square, r1/r2, l1/l2, dpad & 2 analog sticks they for no apparent reason 'Can't" work with the other console. Well obviously you'd need a bluetooth dongle for the ps3 ones with xbox but yeah...standard buttons should work together..
That way I could use the ps3 controller with xbox which would make me very happy, as playstations have the analog sticks right where they should be, as I can't imagine why you'd possibly want left thumb up high & right down low...wtf?
Touch screen display though, eww, lack of feedback just slows things down :( I always find it silly how a touch keyboard for example is harder to 'Touch' type than a normal one :D
Oh & whoever said the lightness was annoying, had a console party last night & every xbox360-er who used my ps3 commented how nice it was having a light controller lol :P