A few words to explain why I hate the Rotten Tomatoes Ratings...
Red means good and green means bad, quite the opposite of Coollector. Having the two in the same interface would be disturbing. This reason alone is quite enough.
Personally I'm confused by the tomato allegory because I don't think it works. A tomato starts green, then it generally gets red, then it rots. Fresh or rotten has nothing to do with the color of the tomato, but normally rotten tomatoes are red
The Tomatometer score is based on the opinion of a bunch of snob critics, and the result is just awful. Some movies are clearly hyped while others are undeservedly crucified. I disagree with almost all the scores. If you're like me, the tomato score has zero interest, a random score would be just as good.
I much prefer the IMDb rating because it's based on the opinion of the users (of course I prefer even more the predicted rating I get from Coollector's personalized recommendations). Also it's cool that the number of votes on IMDb allows to measure the popularity of a movie.