The number of new users will fluctuate a good deal based on where and when there are advertising campaigns or word about the game catches fire somewhere in the world. A few weeks ago, I noticed that one country in particular had a huge spike in sign ups. Just huge. I didn't ask, but I assumed that BB must have put out some serious advertising or got a really great plug or two somewhere there.
Maybe the Olympics will get some people enthusiastic about international basketball and BB will become an outlet of choice?
Don't ask what sort of Chunks they are, you probably don't want to know. Blowing Chunks since Season 4!