Venture capital firm Lightspeed has posted Average Revenue Per User (or per avatar in some cases) statistics on popular MMOGs based on previously reported data. The firm found that popular virtual worlds were able to generate an average $1.25 per monthly user per month:

Club Penguin: $1.62/monthly user/month
Habbo Hotel: $1.30/monthly user/month
Runescape: $0.84/monthly user/month

These estimates were created by dividing each virtual world's reported revenue by the amount of active users on the virtual world.

Lightspeed went on to note that Second Life is monetizing at 5x higher than other casual MMOGs, taking into account revenue from land maintenance fees. The firm estimates that the virtual world averages around $9.30 per account per month, in line with "some of the more hardcore free-to-play MMOGs that companies such as Acclaim, Aeria, OutSpark, K2 Networks and IGG are importing."