You'd be surprised what they've turned down. Don't just assume MS will want it just because you like it, and it's popular. Hate to sound defeatiest, but it's not as easy as "send it to Micorosoft and get it on there". It's a rather complicated procedure, and MS is fairly picky about what goes on there.
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Sorry to sound so defeatist, but individual users won't do much of anything. Now if you could get something on the order of a million people to do the same thing, that might be different, but talking to one person like that isn't going to do anything.

Besides, if you can think of it, they already have - I'd bet on it. Plus as I said above, we've already talked about it ourselves. I talked about this yesterday with George, he's all up for the idea, but we don't have the time to do the port ourselves, plus there's the issue of whetther Microsoft would really want it. Don't just assume they would, there's a big submissions procedure to go through. Plus their release schedule is booked solid for quite awhile now, even if we delivered it to them today, I would imagine it wouldnt' come out for awhile anyway.

It's already been discussed here. Whether it happens or not I can't say. It's ultimately up to Microsoft as to whether they want it or not.