There's an excellent story in the New York Times about all the various sites and blogs that provide travel reviews, mostly from people like you and me instead of professional reviewers. Some of the sites it recommends are:
I also like HotelChatter.com, which seems to have a celebrity fixation, but also lots of fun and quirky hotel stuff. I wouldn't give up the site inspection any time soon, though. Everyone has their own bias, and what might make one reviewer nuts might not bother your attendees at all, and vice versa.