It was always fantastic site for movie reviews in its first 6 years, which always gave a fair average score their Tomato-meter shows for all their readers.
The site was bought by IGN in June 2004, that's when it went steadily downhill. The whole site had to be redesign, making it harder to navigate though it. It also brought in a huge slew of ads, making it even more annoying to navigate.
Still, it was all relatively good. The Tomato-meter was still the same and every movie had their fair share of "fresh" and "rotten" reviews from all the film critics the RT staff can find all over the internet. RT is extremely popular, and they still cared about all their viewers.
This all changed around 2008. That's when it became clear that RT is only in for the business they can get off from certain film "critics" and the hits these "critics" get from RT.
It became clear that Rotten Tomatoes is actually ENDORSING a few trolls, most notably a very consistent one: a hypocritical racist named Armond White who makes sure any truly amazing movie nowadays gets chastised by him. All his rotten reviews consist of comparing the movie he's "reviewing" to other movies he likes (really terrible movies at that). He doesn't mind insulting and condemning the director, the producer, the actors, anyone involved in the film, and especially the fans who look forward to the movie. All he wants is hits his site generated from all the anger and hatred you, the reader, can give him by simply going to the NYPress's site.
And RT helps him greatly with that goal.
Sad isn't it?
Go to Metacritic.com for something more fair. At least they have a rating system that doesn't give trolls much of an upperhand, and they are decent enough to not let morons like Mr. White to ruin the movie with his senseless ilk. There's no reason why Rotten Tomatoes should be around anymore if they are purposely letting trolls ruin real film critiquing.
So don't feed Rotten Tomatoes and especially don't feed Armond White.