I think there is a very good chance the PS4 will come out on top next gen.
The Wii U had a pretty good launch, but is now selling like a dying console. I think the only thing that can turn it around now is a price cut of $80 and a large influx of great games. Even then, I don't see it being #1.
As for the NeXbox, it is going to be incredibly hard to beat the PS4 when they are both launching at around the same price and around the same time. PS4 will already have a HUGE advantage in EU and Japan. And if Sony can convince the core gamers in the US that the PS4 is the system for them, then they can take back some of that market share MS took from them this gen. Which may not be too hard, if rumors are true, and MS is sacrificing some graphical power in order to really push Kinect and Windows 8.
@ BaldrSkies
Trust me, the jump from PS3 to PS4 is going to be quite noticable. The only ones who say it won't are Nintendo fans who are praying that the PS4/NeXbox doesn't blow past the Wii U, taking the majority of 3rd party support with them.







