January is
very unlikely

Though that would be good. Anyway, I'd expect an early April release for the US. Don't ask me why

Then Australia would probably get the game in June

LOL
Australia gets games about 2 weeks after United States of America for most games.
It's freaking ridiculous. I know from a very close source (a Nintendo employee who is a relative of mine) that Nintendo have nearly finished testing and if they wanted, the game could hit shelves by mid December.
But noooo... They ignore the Christmas market and would prefer people buy the Wii and Ranger (crap) while they wait for the game to generate some sales for the Wii and Ranger instead of people only buying D/P.
This source informs me that they are regularly updated with progress of much-anticipated games to estimate release dates and devise marketing strategies.
The game should hit USA shelves March 2007.
Please don't refer to it as "Spring 2007", not all of us live in northern hemisphere.