IMedExchange, a social network for doctors, is launching with $2.5M in angel funding. IMedExchange hopes to create a place where doctors can openly exchange medical advice, business tips, and chat. The network is open only to practicing physicians. Thirty-eight out of the 40 angel investors in the company's $2.5 million financing round are physicians. An additional 225 doctors or so have received a small equity stake in the startup as part of joining the company's advisory network.