If it were MercurySteam by themselves, I wouldn't really be that interested. But since it's Nintendo, they would likely work first-hand with MS and watch them like a hawk (see Metroid Primes, DKCR, Punch-Out!!!, etc), so that could end up being very interesting.
I imagine Nintendo would sooner hand it to some studio they've worked with a lot already, though. Whatever Nintendo's gotta do, I just want a new 2D one.