When I'm looking for people's opinion I want to know at least a little about the people and have more things in common with them, so that we have similar tastes. IMDB is almost useless for me, people like complete crap imo (is there any movie without at least one 10 star rating? That should be the single best movie ever). If you wouldn't fit in the community, the community's opinion on things is largely irrelevant and whether you look at the opinion through a histogram or a scatter plot is irrelevant.
If you actually have friends, why don't you ask them for recommendation in person. If your friend is really into arty movies and recommends you an arty movie as being very arty (and well done) you can consider it. Collapsing it into a single number doesn't make sense </rant>
EDIT: that's not to say that the scatter plot isn't an interesting idea, it's just not going to help much because people's background is important for rating
You've absolutely hit the nail on the head. Knowing the rating of a friend is worth so much more than a bunch of strangers. That's what Goodfilms is all about - it puts your friends' opinions ahead.
If you actually have friends, why don't you ask them for recommendation in person. If your friend is really into arty movies and recommends you an arty movie as being very arty (and well done) you can consider it. Collapsing it into a single number doesn't make sense </rant>
EDIT: that's not to say that the scatter plot isn't an interesting idea, it's just not going to help much because people's background is important for rating