I've expected it for a while now actually, with Zelda: Ocarina of Time 3D probably launching late June or so, I don't see Skyward Sword arriving until September or later. It's all going to depend on what else Nintendo has on offer for 2011, for example we know Nintendo have Pikmin 3, Wii Relax and a new IP from Miyamoto (unless internal plans have changed) and so they could potentially have a heavy back half of the year.
I see it possibly like this:
Q1:
- Kirby's Epic Yarn
- Mario's Sport Mix
Q2:
Absolutely nothing.
Q3:
- Pikmin 3
- Wii Relax
Q4
- The Legend of Zelda: Skyward Sword
- New IP
What I'm unsure about though is whether Dragon Quest X is going to come to japan this year.. I can see Pikmin 3 being delayed to 2012 if Dragon Quest X is coming to Japan as it may be too many games in the latter half of the year. It's also possible that Wii Relax has been shelved, in which case Pikmin 3 could be the only game from Nintendo over a 6 month period on Wii.
If Zelda is coming earlier then the release schedule could look like this:
Q3:
- The Legend of Zelda: Skyward Sword
Q4:
- Pikmin 3/Wii Relax
- New IP
It's also possible Nintendo will cut the price of the Wii during Q2/Q3 if sales momentum drops off too much. I don't see it happening right now, but it's a possibility.