Very cool project!
I'll have a look at it later today, but have a quick question-

is this just connecting to the sites like a normal web browser- port 80 http connection?
(wondering from a security perspective as I might try to connect at work behind a strict firewall that may not allow all traffic out.)

Also I think having it update once every one to five minutes is probably fine.
Unless you are doing real-time trading the price of BTC moving over five minutes is probably not that much to cause any issues.