As far as I know it does do some caching (or at least I've heard @usernamecheck (http://www.twitter.com/usernamecheck http://www.twitter.com/usernamecheck) twee

As far as I know it does do some caching (or at least I've heard @usernamecheck (http://www.twitter.com/usernamecheck http://www.twitter.com/usernamecheck) tweet something to do with caching).