GM just noticed that Google has added real-time predictions for the Circulator. This way you check when the bus will be coming before you leave the house.
To use it, load up Google maps and zoom in on Georgetown. Right-click on the blue bus icons for your stop and the bubble will open up telling you when the next bus will come.
The Circulator is supposed to come every ten minutes, but it’s not always on schedule. So it’s worth it to check before heading out.
Unfortunately, Google still hasn’t worked out a deal with WMATA to provide real-time information on normal Metrobuses, so the bubble only gives you Circulator predictions. (Until they do finally work something out, you can still get WMATA’s predictions at Next Bus.)
Update: Turns out GM was wrong. It’s not real-time data, it’s just the schedule, which isn’t very accurate or helpful. Until Google works something out, use something like this.
The Georgetown Metropolitan 
There is a Circulator app for the iPhone but it isn’t as good as the NextBus app. The Circulator app just tells you where the bus is supposed to be and how far is it from your current location.
These are not real-time predictions! These are just the times when a bus is supposed to be coming by, hence they are always 10 minutes apart. Any transit agency on GTFS has this enabled with their scheduled times (no real-time yet on Google for ANY system).
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