If a game is still at 30fps, it isn't a deal breaker to me. I mean you do notice when games are 60fps (smoother) but there's very few that really benefit from the higher rate. Mostly racing games or anything that's really fast paced. Sonic Generations for example is vastly superior on PC for that reason. All broadcast TV is 30fps.
I do however think 1080/60p is something we need to be striving for today.
As for Nintendo pushing out new hardware anytime soon, it would be a bad move. Sega tried this when they released the Dreamcast so soon after the Saturn came out. Upset a lot of their core fanbase, who felt they'd been cheated. Gamers aren't keen on the annual or biennial hardware releases you get with mobile devices. Nor will they be unless you could guarantee indefinite software compatibility and a $200 price tag.