You need to use the link from the MO 2.0 (second post, first page) which allows a login. Otherwise you just get a notification of a private beta going on.
]]>http://dev.mathoverflow.stackexchange.com/q/103749/5094
? [Note: this question is in the MO 2.0 sandbox--not the actual site, where I would not have the nerve to ask it.]
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