The Wii U might outsell the Xbone, but that doesn't necessarily make it a successful console. In fact, the Xbox One has the potential to redefine failure, in ways never imagined before. Years from now, we might look back at the Saturn or the Dreamcast, and consider them successful, compare to the Xbone that is.
To the point:
The PS Vita is a handheld console. The market for these devices is barely 15 million units per year. As if that wasn't enough, some genius over at Sony thought it was a good idea to use overpriced proprietary memory cards for the system.
Home consoles are a much bigger market. So far I haven't seen any huge mistake made by Sony for the PS4. Sure, pay 2 play online will alienate a great many customers, but I believe this is a decision that will bring a lot of profit in the long run. Millions of sheep paid for Xbox Live Gold so there is precedent that suggests this choice is right, from a business perspective.