I've only done the film version so far, because I rate more films currently. I'm now adjusting my existing ratings on RYM to match it (slow work).
See what you think and please offer feedback.
0.5 - Reserved for movies I tried to watch and switched off before the end. The kind of movie that makes me question why anyone thought it was a good idea to even make.
1.0 - This is a really bad or boring movie, reserved for the worst of the worse providing I at least got to the end, at which point I wonder how I made it and question my sanity for doing so. Some movies that initially get a 1.5, 2.0 or even 2.5 may end up here if after a couple of weeks I find I can't recall a single thing about them.
1.5 - Worse than Paris, Texas, a movie I absolutely loath but still manages to fall into the 2.0 group. 1.5 movies, in hindsight, seem like it was ill advised to watch them and I wonder why I did, since the warning signs were probably there. Their only redeeming feature is that they're not 1.0 movies.
2.0 - A poor movie, but there might be redeeming qualities, like some genuinely good bits and hints of potential that wasn't capitalised on. Upon it's conclusion it won't feel like a complete waste of time and that it was worth giving a shot. It just didn't work out.
2.5 - Some good stuff, mostly poor. Movies I keep of this rating or below are part of boxsets that I don't want to break up or owned digitally. Franchise movies are only safe from being thrown out if not having them creates plot holes later on if trying to watch the whole franchise right through.
3.0 - A good movie, but one I'm left with no desire to watch again. I generally won't want to keep a movie rated at 3.0 in my collection, with the exception of certain franchise films (Spin-off franchise movies like The Bourne Legacy are in trouble though), which I'd re-watch as part of the whole thing but not as a solo entry.
3.5 - Pretty much the same as a 3.0, except I feel more confident that I'll watch it again eventually. 3.5's may also have potential to open up with a second viewing, so they're worth keeping until at least the second watch.
4.0 - This is a very good movie which I will definitely watch more than once and probably more than twice, but not with any great frequency. Enough time will pass between seeing it that I'll probably have forgotten all but the best bits.
4.5 - This is a movie I'll watch a lot. It's entertaining from start to finish, with absolutely nothing that bugs me in any way, but I can't quite rank it with my all time favourites. Most movies I loved will use this rating. It's also the highest I'll give on a single viewing.
5.0 - I expect to watch this movie many times over. I can even watch it again a short time after last seeing it. I probably won't most of the time, but I can and it'll lose nothing. It's an all time favourite. Reserved for the very best of the best. Movies can't earn this rating until they've been watched at least twice.