the 360 is already the winner of this gen, perhaps not by sales but by the fact that microsoft is in a far better position in the console market, their user base has grown exponentially and that will have an effect on the following generation. they've done their job, they've proven that they can make a good, solid console and can support it well (and acknowledge their faults and take steps to fix them), the games are good, and there is a great selection, live, although it costs IS the best online console service in place and they've done their job at securing additional content for new games (looks at GTA IV).
whats more to be said. microsoft have done the best in this round. they've severely narrowed the margin with sony and the next gen should be on a more equal footing and less david versus goliath.
on the subject of the wii: i have a few friends that have this, from my observations it seems to be a console that is largely used as a tag on, or as something the whole family can play, once the novelty wears off it gets left in the corner whilst it's owner plays away PS3/360. they've made sales, but i don't think they've really made a great impact. i and many others view it as more of an accessory to the bigger brothers, i know no one with a wii as their only console, it's just not good enough.
edit: not a fanboy, owned and loved every main console in the last gen, loved playing on the wii (but got bored quickly) and i think the PS3 is a really good deal and good to play on (bar the controller which i find painful

), i own a 360 purely for its exlusives for nothing else (and neither of my 2 have broke, one from the first 3 months of launch and one bought this week so i don't really have anything to complain about in regards to the 360)