Virtual Worlds Registered Accounts

There's a really interesting graph showing information about different virtual worlds posted on Virtual Worlds News. In addition to the number of registered accounts each world has, the graph also shows the target audience, growth since launch, and their launch status (active, closing, open beta, closed beta, etc).

No huge suprise, the worlds with the most registered account include Habbo (by a longshot), Neopets, Stardoll, and Club Penguin. My personal favorite, Free Realms, is on the graph with a strong 3 million users, which I think has recently been increased to 4 million. Some of the big winners in 2009 include Club Penguin, which gained 6 million users and Nicktropolis gaining over 3 million.

http://www.virtualworldtimes.com/.a/6a00d8341cac2153ef0115720a8ff2970b-pi

Sure are a lot of virtual worlds out there. I hadn't even heard of some of those prior to reading this, although I played/have played quite a few of them at some point.

UPDATE: Just found the article about Free Realms passing 4 million. I knew I saw it somewhere a while back, but couldnt find it. Thanks to VWN for posting a link directly to it! LOL
http://www.freerealms.com/article/detail.action?cid=1053341,EM960&articleId=134