The Robinator also uses this app while training for his marathon: RunKeeper
I downloaded it too to see what it was all about. When I was setting it up, I noticed that it has different training programs built in to help you train for different runs or walks. I have a girlfriend who has a goal of doing a 5k in the near future so I sent it to her. The training program seems pretty reasonable and nothing that will kill you. LOL!
How many of you runners use RunKeeper? Do you like it?