The question is in the title. Your thoughts.

They have so far I don't see why not.

When they have ggod games they can, but as we saw earlier this past year, when the games dry up, the Wii stalls.

They can do it, they just need the games.

I can tell you more clearly, but first do you know about magic and its relation to business?

Yes they can. But with the release phase of one publisher, a misjudgement of the market/a flop like Wii Music ends up ending the momentum because a title that could fill the gap isn't going to come in time to fill it.

They can and they must be planning to do so

The right software will totally do it. The issue is that they really need to strike gold to get momentum going, a steady diet of just good games isn't going to cut it. They need magic.

Been doing it so far by themselves.

They don't need to, they're getting 3rd party support. :p
Sure it may not be the best, but we're still getting stuff like NMH2, Red Steel 2, DQX and MH3.