Well, It's not needed for portable gaming.Hum... Not to be out of topic, but seriously, the "Let's make it for the Vita instead" line isn't going that well so far. xP
Adding dual analogs is pretty much common sense. It's been the norm for console gaming for well over a decade and we now have the technology to make it on portables. Why is it not there yet?
If you enjoy having a camera that isn't complete shit then yeah it is.
Portable games are hardly 2D anymore.