"People have been ignoring the fact that there are 12 other virtual worlds out there that have hundreds of thousands of visitors," says Jonathan Nelson, special adviser to Omnicom CEO John Wren. "My bet is this stuff is here to stay." Omnicom recently took a significant stake in Millions of Us, and the Wall Street Journal story gives a fair amount of time to Millions of Us projects. The main point, and one that  developers like Millions of Us have been touting for a while now, is that virtual worlds are prime for advertising, but Second Life isn't the only or even the best option out there. Based on Comscore figures for the month of September, Second Life ranked at the bottom of 12 worlds in numbers of unique visitors. And, yes, the number (235,000 for last month) is drawn from users accessing the software for the world, not just visiting the website. Even the rapidly declining Millsberry.com--down 17% from last year, but still at #5--saw 2.5 million unique users.  Webkinz led the pack with 6 million unique users. [via WSJ.com]