Playstation Vita = 32 million
Based on what's known right now, I think it's a safe bet. I don't expect the system to sell that much on its own merits, little over 20 million, but PS4 integration could push it higher. That said, I won't know til E3 what's in the pipeline, so I'm shooting a bit high.
Wii U = 20 million
I consider that a fairly optimistic estimate. It sold great it's first month or so, but now it's on track to fall behind the Playstation 3 by the end of the month; the Xbox 360, by mid-May. And if there's anything coming in the next six months to change that, I haven't seen it.
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