The dream is still to try to automate arbitrage trading across multiple exchanges and markets, just like everyone else I'm sure ...trying to go beyond the usual buy btc/usd here and sell usd/btc there.  Main blocker right now is that every so often you need to re-balance funds across exchanges, but most exchanges don't have have an api to do transfers/withdraws.  Writing robots to login for you gets kludgy, and sending alerts to go do it manually is too burdensome.

For that project I just had this data collection running on a single host.  But I realized that if I wanted to open this data up I needed to distribute it across several nodes to make sure there is never any down time.  As a side benefit I am able to get past some of the rate limits imposed by exchanges because I am coming from different IP's.