I'm the creator of JamRides. This is my first webapp, so please feel free to throw me whatever you can think of, especially the obvious.
FYI, I decided to leave out anything that explains what JamRides is about on the homepage, (check the about section) mainly because I don't expect anyone to come to JamRides through homepage linking. In fact, the main feature of JamRides enables anyone can post carpool links anywhere, so the traffic coming in will should already know what we are about (somewhat).
Does this make sense?