If you are starting up a web, mobile, or standalone application, how well must you know the rest of your collaboration team? Would it be a bad idea to ever work with someone unless I've met him personally? Is it okay to sometimes accept small public contributions such as code snippets and artwork without meeting the contributor? Should I ever actively collaborate with people online that I have not met, as long as the person has a detailed profile and a good reputation.
If you do collaborate online, what tools do you to build teams and find contributors? If not, would you consider the idea if there was a safe medium? Any other input on the subject would be appreciated.