Honestly I was really surprised they mentioned their exclusivity contract with Microsoft.
The 360 port of Minecraft is a timed exclusive, Microsoft doesn't deal in total exclusives anymore and most devs turn around and use the bags of cash they got to fund ports to other platforms - it's a win win, because they don't have to spend money on porting their game to other platforms and by putting it on more they just get more money.
Jeb even said that they have to wait for the exclusivity contract to run out. If he said that without fear of repercussions, I'm pretty sure that means there's a decent chance.
I doubt anything else Mojang does will ever top Minecraft so they're gonna ride the Minecraft wave as long as they can, IMO. I think it's perfect for a handheld (look at how well PE is doing) and the Vita has the best control scheme IMO, so hopefully we see it soon.