Depending on when they initially announced it, I'd say they should take their time with it, like they did for TP. About a year and a half from now should be good, so:
I retract my initial estimate given that Nintendo said that there is a small chance it might be released in Japan by the end of 2010 and no chance of it being released in North American by 2010.
I'd say since Nintendo wants to get it out their by November 2010, and we've seen the delay in TP, it might hopefully be out by Christmas 2010-January 11th 2011.