Yes and No. If a trailer looks good and the critics are not very good, I'll still watch. Critics are also a great way to watch movies that you didn't want to see at the first place.
Not at all... Music, especially commerical cannot be judged by group of people, when it just comes to the taste. That's the difference in movies and music. You can tell when movie is good, you can really tell when actors are amazing in parts, but in music? When everything is sooooo commercial, how can you listen to group of people who tries to judge? Especially Grammy's... Beyonce has 100's of them, and will get another 100 this year, but does she even care? She would prefer to have that one OSCAR. Critics don't matter in music, Britney has only 1 Grammy (not amazing voice, though), but she has had amazing career, so I don't think she cared, she wasn't even on Grammy's. Avril lavigne doesn't have a Grammy, did she care? IDTS.... Man, I love Katy Perry but no one will tell me she's better singer than Avril but Grammy's do tell so, so there's that. I don't care about music 'critics'.
Critics do matter in movies AND in music. It's fine if you don't care, but they certainly do matter.
Yes. I may like something, but my enjoyment of it doesn't mean it's good, which is where I go to reviews. Pitchfork or Consequence of Sound means much more to me though than Billboard and Rolling Stone, and if you expect me to delete an album on iTunes because People gave it 2 stars...