The case FOR seeing movies on opening night: Um, it's awesome? Surrounded by people who are just as excited about seeing a movie as you are. Staying up real late. Knowing that you are amongst the first to see what, in the case of The Dark Knight Rises, is an incredible film. You'll be able to talk about it the next day, and best of all you don't have to worry about spoilers.
The case AGAINST seeing movies on opening night: It's crowded. Lines. The theaters are always noisy. And what's to say you'll even get in just by showing up if you didn't preorder tickets? May be better to wait a week or two (or even a day or two) and see The Dark Knight Rises when things are (slightly) calmer.
Indeed, this may be more of a general argument. Me? I wish I could go see it opening night. I love doing that. As it happens though, I won't be able to get to a showing of The Dark Knight Rises until about a week after it comes out. I know. You can't imagine how annoyed I am about that. Expect a review sometime around when I can get to see it.
When are you going to see The Dark Knight Rises? Whenever it is, this 13-minute featurette should be able to tide you over: