Seriously, and think about it: Nintendo's remasters have sold well. Wind Waker HD, Ocarina of Time 3D, Majora's Mask 3D, etc. It isn't out of the question that they'd have commissioned another remaster for this holiday season. Mario Galaxy would be a great game to choose.
Hm, I thought they said SMG port was the prototype that became 3DL because it didn't run as they wished? Maybe they got it to work better... or, maybe they got it to work better on N3DS but I would be very surprised if they released such a major title as a N3DS exclusive (and the 3DS remasters have definitely been major titles for the system, as you said).
Of course, a SMG3 would be even cooler, but, see my reply below.
3D Land 2.
Please Nintendo.
Seemed likelier before Miyamoto-san's E3 comments regarding seeing a new Mario next year (implying, at the earliest). 3D seemed implied but it was unclear.
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I don't want to be shooting down any Mario games' likelihood of coming. I want very badly for them to come. Just trying to temper my expectations a bit.