Weddings- What's important, what isn't?

I am planning my wedding (woo hoo!) and have been receiving advice, both solicited and not so much, from practically everyone I know. I’ve only been to a small number of weddings myself, so I don’t know what advice to take.

Some people say “don’t worry about the cake, but don’t skimp on the photographer! It’s the best investment you’ll make!”. Some people say “just hand out disposable cameras, but make sure your music is super!” Some people say “your guests won’t care about the food, but they’ll remember your flowers!”

I know that the bride and groom set the tone for the day, and that even if my cake collapses and my flowers wilt, I will be super happy. But for those of you who are married or frequent weddings, what do you think is important?