I think a lot of what will happen is dependant on a few factors:
1. Nintendo's success is purely based on being able to inspire the current gamers and being able to woo the non-gamers. The non-gaming community are Nintendo's biggest secret weapon in the next gen. Whether they respond or not is completely down to the games, which should appear more regualrly than this gen.
2. Download service. If the catalogue for download is extensive and inexpensive then I see loads of people buying the Rev as a second console as it has a huge games list which is (most importantly) only a click away.
3. PS3's price. I have a very funny feeling that Ken's ego is getting a little obese and he could end up screwing everyone big time. He's been saying some weird stuff, like how people should do overtime to afford their PS3 and that its a premium product. Wouldn't surprise me if the PS3 releases at over £400-450. How many Revs could you buy for this?