One thing that really bugs me... isn't so much in the movies themselves... but whenever a tv network censors stuff. It's one thing to censor a swear word, but it's another thing to take out stuff that was part of the movie originally and then have it not make any real sense, post censor.
And a side note from that, I hate when they cut from a movie for a commercial and when you get back, you're in a part of the movie that has
nothing to do with what you were watching previously

.
Editing my butt.
Yes, this is an interesting one.
Due to the fact I've only ever seen Robocop on TV and its scheduling here (our TV schedulers seem to think Robocop is some kind of kids movie!) I still have no idea why a light slapping from some felons leads Murphy to suddenly need to be maintained in a Robotic Life support suit!
I get you have to edit that scene but, c'mon, leave us SOME context.
Sadly censors don't usually get their job because they're good with the editing machines once they've made their decisions on what we should or shouldn't see on our behalf!
Another overused effect that's getting on my nerves is a camera trick I learnt in my first year of college on a media studies course yet some movies seem to treat it like it is the most amazing and hard to pull off technique in filmmaking!
I'm talking about when they zoom in while physically moving the camera away from its subject (or vice versa), usually to denote a "Eureka" moment.
I think the first time I ever saw it was in Scrubs but after that everywhere I looked, it was there.
I don't know its technical name or too many examples of it being used off the top of my head but hopefully my description is approaching adequate enough get some other people's brains firing as to what I'm referring to!