It's going to be hard. The Xbox brand is not as big as the Playstation brand and it doesn't look like it's going to gain much traction this gen. Basically, Playstation would have to pull an Xbox One and Nintendo would have to pull a ... Wii U. Hm.
Outside North America, it would be a real up-hill struggle. They'd have to score a clean win in terms of games and hardware, as Playstation would almost certainly win with a tie on those fronts.
The good news is that every major console manufacturer has stumbled at least once over their own arrogance. Sony twice, Nintendo twice, and now even the new kid on the block, Microsoft. It's certainly not outside the realm of possibility for both Sony and Nintendo to fudge up in the same gen.
One strategy to gain market share would be to kill the Xbox One early and grab a head-start. It worked before.
