Well at least this thread is realistic, unlike the other one talking about lifetime sales.
It's really hard to say at this stage. I would expect a somewhat weak PS4 launch. The mass market is going to be very happy with GTA5 and COD:Ghosts on their PS360. KillZone, DriveClub and Knack are hardly exciting reasons to pick up a $400 PS4. That said, there are lots of hungry Sony fans ready to snap one up.... I just wouldn't expect mass hysteria or Wii-level hype.
So assuming at least the very high-level of launch interest that Wii U enjoyed last year, more supply and an earlier launch, we could see 3-3.5 million PS4s sold this year. That would mean Wii U would need to sell about 2-2.5 million units at Christmas. Gamecube usually managed to shift at least that much in its first few years, so I would expect Wii U to outsell PS4 in 2013, even in a best-case PS4/worst-case Wii U scenario. If Nintendo takes aggressive measures such as a price cut or heavy marketing, Wii U could possibly exceed PS4 in fourth quarter sales. It will be interesting to watch.
