I find it most encouraging that it's coming from the head of their mobile department, because that means the mobile games might be of better quality.
I just played
Batman for the Gameboy for the first time. This is a first-generation Gameboy game. The controls are tight, the powerups are cool and the game is well-balanced and designed. Batman, of course, looks adorable in chibi form, but you stop noticing once you get down to playing the game itself.
You can make a good game on a portable device, it just takes work.