Sooo... when the commitment phase is finished, that's going to be a lot of questions!!
I don't think they really expect everybody who commits to ask 3 questions. Remember that they're being extra cautious with the first round of SE 2.0 sites; they really want to make sure that they're going to be successful. I haven't been following the commitment numbers, but I'd bet that Mathematics won't be among the first new sites. Once a few sites have been running smoothly for a while (a month?), I expect they'll loosen up the requirements. After all, a promising site never seeing the light of day is a worse outcome than a decent-looking site going to beta and then flopping.
]]>On a slightly different point, it seems harder to find the "superusers", e.g. Anton, who are willing to put a lot of time into managing the site, at a higher level than dealing with individual questions. Of course, the whole point of Stack Exchange is that this role isn't actually meant to be too much work, but I'm still dubious.
]]>I'd also note that the 'real name approach' you see on MathOverflow is no accident, or inevitable with the available software. The moderators worked at this pretty hard in the early days, emailing new users as they arrived explaining why using real names was a good idea.
]]>A general mathematics StackExchange site has already been proposed: http://area51.stackexchange.com/proposals/3355/mathematics
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