I'm a fan of Bill Maher. He's not my favorite comedian (that distinction would go to Robin Williams; his stand-up comedy Live at the Met still makes me laugh) and his humor is frequently hit or miss, but he does provide moments of pure genius. His "documentary" Religulous scored some hard hits, but he enjoys a lukewarm reception at best from the atheist and skeptical communities.
I find it ironic that Stephen Colbert, who in his private life teaches Sunday School is more popular with atheists than Bill Maher who goes after religion like a rottweiler with a sore tooth. We swoon over Hitchens in spite of his neoconservatism and make excuses for Dawkins' dismissal of feminism and male privilege. They're all controversial positions and where people stand on them is of less interest to me than the fact that the atheist and skeptical communities still show them unconditional love -- but not Bill Maher.
Maher fucked up with his opinions on vaccinations. He failed in his skepticism on the issue. But since when does a single issue invalidate everything else he says or does?