April or May 2012. If NIntendo really does intend to have a similar launch strategy to the one of the 3DS, then it doesn't matter what they do anyway. They are going to be screwed.

Think about it. When it comes to handhelds, Nintendo gets good third party support, because there's no alternative. Sony largely failed with the PSP, so ignoring Nintendo is not a viable option. But when it comes to home consoles, Nintendo can't fall back on such a bonus. They are going to get half-assed launch third party software and with no first party hit available the console struggles out of the gate giving third parties all the justification they need to never improve their support. Nintendo ends up with Wii like third party support and without Wii like hardware sales, because the console will be written off as disappointment pretty much immediately.

In the end if it's just another console, June isn't a great time (if it even drops in June).  If it's another 'IT' thing like Wii or Ipad then regardless of when it drops they'll be no keeping it in stock.   Until I actually see 'Project Cafe' I'm not making any assumptions as to it's success.