Michael Sam is going to be drafted for his football ability, and because some team believes Sam's usefulness as a pass-rusher can help it win. How useful he can be is a question, because the sample size of really good play from him is small, and there are questions about his versatility. But he has the potential to help a team, and I've had him as a likely early third-day pick for a while. I still think that's a likely landing spot.
Will his announcement hurt his stock significantly? I don't think enough to keep him from getting drafted. A few reasons: