This is easily one of my favorite additions to the ISY. I've never been thrilled about outsourcing my geofencing to IFTTT and now I don't have to. I'm probably most excited about the [future] prospect of tracking multiple locations (home, work, gym, etc.) and using those to delay certain programs such as heating and cooling. A few other requests would be the ability to pass lat/long to the ISY as variable as well as battery percentage. I would use the battery percentage alongside the Alexa Tell Me functionality. Passing lat/long could be a substitution for multiple location support I suppose. I also noticed that icloud.com now has the find my friends app. Would be cool to incorporate that in a future release.
In the interim, I'm considering running three instances of script and triangulating my position from 3 different fixed points. (2 mi from A, 3 mi from B, 5 mi from C = work)