I have to be honest, I get like that too. Not so much with good reviews, but when people I know tell me specifically I have GOT to see something, after I hear that too many times there's a part of my brain that goes "Fuck you! You're not the boss of me!" It's totally stupid but it's a knee-jerk reaction I can't really do anything about. Then I'll hold off on checking something out until I know the idiot resentment towards it has passed and I can give it a fair shake.
This is, incidentally, why I have yet to watch Community or Dr. Who.
Thank you to Dorkman for saying it better than I...
Though, you really should watch Doctor Who...just sayin'