I've been approached once or twice about what exactly my rating system is, so here's the basic rundown:
1 outa 10
This is the worst movie I have ever seen. Walked out of the theater and have made it my life's mission to burn all existing copies.
2 outa 10
Wow, this was incredibly awful. The plot makes zero sense, the acting was terrible, and it was horribly filmed. But maybe there was a random character or two in there that made me giggle a couple of times.
3 outa 10
Yikes, terrible. Had a couple of laughs, the acting was still pretty damn bad, and the plot only sort of made sense. Had much more potential but simply did not get there.
4 outa 10
Pretty bad, but mostly due to logistics and some bad acting/casting choices probably. Again, the plot got jumbled in itself and didn't make much sense.
5 outa 10
Mediocre. Not memorably bad but not very memorably good either. Most likely churned out by Hollywood.
6 outa 10
Pretty good. Would probably see it again. Acting was pretty nice, plot could've been a little better, or maybe there were a few loose ends that never got tied up. Still, thought-provoking at least a little bit.
7 outa 10
This was very good. Good acting, good casting, good sets, good plot. Interesting, thought-provoking, and I would recommend this. There was probably at least one gasp. I thought about this movie for a few hours after it ended.
8 outa 10
This was really REALLY good. At least one of the characters totally blew me away (if not more), the plot was above average, there were emotional peaks that may have included tears/lolz/screams/etc. This movie was stuck in my head for a day or two. I want to recommend this movie to people even if it wasn't brought up in conversation. People should see this and I feel obligated to talk about it.
9 outa 10
I was smiling/frowning/wide-eyed/appropriately emotioned throughout the entire film. The actors were all spectacular. The sets were fabulous. The plot was perfectly executed and thought-provoking. I was thinking about this movie for days after I saw it and rambled about its themes and characters to excess in front of people that probably didn't want to learn as much as I gave them. I adore this movie.
10 outa 10
I am incapacitated by my love for this movie. I was blinded by its amazingness. I have taken to the streets ranting like a lunatic about how wonderful it is. People are frightened by my enthusiasm for this film.
Hope that that more or less clears everything up. One thing to keep in mind, however, is that the ratings can be skewed by entertainment factor as well. For instance, cult movies like The Room or (an old personal favorite) Babycakes can move up the ratings ladder by being so ridiculous that they become entertaining.