The only major problem I see there is battery life...
90 minutes to 3 hours...
I agree with the people who say battery life in handhelds doesn't need to last friggin like... 8-10 hours or whatever Nintendo gets out of them (just plug the dern thing in at night and problem solved, you're not gonna spend 8-10 hours playing it in one day, or at least you shouldn't), but as low as 1 1/2 hours?
My guess is they'll find some way to fix this problem... Such as... Super... Batteries.... o.O