Now I flat out will let you know that I am not an expert on all things about virtual worlds and MMOGs. But I do know a thing or two about databases 
. And I do know about game data and some of the challenges and requirements for their management. For starters about how Informix capabilities can help manage game data, check out this white paper I developed – Fun and Games: The Data Server for Interactive Entertainment.
I look forward to your feedback and comments!
If you are new to Informix, I recommend you visit the IBM site for Informix.
And if you still need some real life validation that database technology matters, read this article on why one company Icarus Studios, switched to Informix.
My colleague George Dolbier, who is a well-respected IBMer in this industry has this valuable article on sizing.
Also, here is a nice article by David Kennerly on aspects of game data mining. If you are an MMO developer, this article gives you good insights into why (and why not to !) , when and what data to mine from your game.
