Is this something you need to have in some of your Rails project? Maybe you'll need a blog + a e-commerce framework like Spree? If yes, what are the features you are looking at?
Might fail, might succeed...only time will tell! It isn't a Wave 2 that no one will understand, but still have rough edges, bugs, no API (no integration with apps besides official one), nothing major that could make ppl move from Facebook, might be hard for casual user (think your father and mother) to get a Google Profile as Hotmail users...etc!
https://developers.google.com/maps/documentation/geocoding/#...