First: I can't believe I've overlooked this thread. I'm backing Kevin up here.
I hate shooting weddings for all these reasons. Mostly, because few people really know how much stuff costs. On occasion I'll get talked into it by a friend or co-worker Even then, people are shocked when I charge cost for a roll of film at $30.
That just covers the film and processing given that I'm not buying Eckerd brand film and having it processed by some mouthbreather at Wal-Mart, who might remember to close the lid on the processor when he runs the film of someone's wedding through the half exhausted fix tank. There's no room in that $30 for my time.
Two: Whoever said, "Read the contract," is the guy with the right answer. Regardless of what the law is, your specific situation is determined by your specific contract. If nothing is written in about transferring copyright, it belongs to the photographer.
Three: Adam's Cornell links don't address photography specifically. Go back and do more homework. Try photo.net.

Search the forums for specific links to photography copyright.
Four (this is photog-geek hairsplitting):
Kevin Allen wrote:
But if you sold it to the local newspaper (or Time magazine, etc. ) for a story on weddings, you wouldn't need permission. (but the more ethical photographers will get permission anyway)
There's a fine line here Kevin. If a photograph was taken within a certain set of parameters and it's use is journalistic or documentary then there's no ethical issue in not getting a model releases for anybody or anything in that image. Photogs for the N&O don't get permission from anybody in a photograph that appears in their publication or even if it gets picked up by AP.
However, if that same image is to be used for advertising that changes everything.
Two true stories:
One: A doc-photog friend of mine did a book on horse racing out west, Cadillac wanted to buy rights for use in advertising. The photographer had no model releases. Instead he had GM's ad firm sign a contract stating that if any litigation came up it'd be on them and not him.
Two: National Geographic started overusing that McCurry photo of the Afghan girl for promoting a
lot of NG stuff. People accused them of taking advantage of the fact that there were no fees for using the girls image. Geographic finally caved and started a fund specifically for educatiing Afghan girls and has backed off on using that image.