Silicon Alley Insider is attempting to rank the most valuable private web companies in the world. The list is of note to this blog largely because it contains a number of entries that are MMO/Virtual World-based. (of course, please note that as these are private companies and as Silicon Alley Insider has no privileged access to their financials valuing these companies is really nothing more than a somewhat educated guess).

Facebook tops the list, of course (though at $9 billion rather than the $15 billion valuation Microsoft invested in), but Webkinz is #7, Habbo is #9, Linden Lab is #11, and Stardoll is #17. Bafflingly missing is Runescape/Jagex, which it seems to me should be somewhere around where Habbo is.