1. Why would I want someone to ssh into my machine -- at least with the frequency that a service to help me do it is valuable?
2. How is this easier/better than saying 'hey bro whats your ssh pub id? -- eh.. do `cat ~/.ssh/id_rsa.pub`
Over all this seems like a tool that only super technical people would ever use, and for those people adding a key to authorized keys is trivial.