Also, I'm glad you informed us about Riak deployments, but the last statement is inappropriate: please don't be rude. And spelling please as "pls" makes you seem immature too.
Another customer, Electronic Arts, uses Basho infrastructure for a system that supports 7 million daily users of Warhammer Online on Facebook, saving each player’s status every half-minute, Falco said.
That's an impressive number of daily users, but it's just saving a status every half-minute? I don't see why MongoDB couldn't handle that just fine, assuming enough nodes (auto-sharding is basically working now right?).
Personally I am not at all worried about having to deal with 230k writes/second, though. If one of my apps ever gets that large, I will expect my far-smarter-than-me head of DB ops to deal with it, then send me an email telling me all about how he'd solved the problem, which I will read with great interest from on board my gold-plated yacht.