It varies. I'd be lying if I said mood wasn't involved. But I ask questions like: 1. How responsive are the startup founders when I e-mail them about pr

It varies. I'd be lying if I said mood wasn't involved. But I ask questions like: 1. How responsive are the startup founders when I e-mail them about problems? 2. How portable is the work I'm going to put into the site? Data portability is actually probably my number 1 concern. 3. Does the service give me value that I couldn't create with my own server after an hour of coding? (Why would I sign up for yet another contacts service when I can host my own LDAP server for free?) 4. Is there a vibrant community supporting the startup from the get to? At least these are the first that come to mind.