Of course it's possible, Microsoft have beaten Nintendo before, and are currently beating Sony. Even if Sony pulls ahead it proves that if they come out with something better than the rest they can beat them both.
Wii mote was a gamble, Nintendo had faith obviously but it was a gamble nonetheless, they could come out with even more inovation next gen and it go completly tits up.
Sony I feel will win next gen, winning a previous gen by tens and tens millions more than the competitors does not mean it's likely you'll win the next gen. I feel Sony have learnt from their mistakes, the only thing that could harm them is the smaller userbase of the PS3 going onwards.
Going into next gen, Microsoft are the ones that need to work the hardest, they need to come out first and they need to have something stunning.
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