We (Tyler and the kids) had a chance to see Deathly Hallows part 1 early last night (no we didn't stay up until midnight). There was a Boy Scout leader who coordinated with a local theater to have a showing for scouts and families. The atmosphere in the theater was nice and we didn't have to fight a huge crowd.
I must say I was pleasantly surprised. There were some changes from the book (we didn't even see the invisibility cloak) but nothing too out of line (burning down the Weasley home). They didn't seem to keep themselves concealed or hidden in the movie as much as they were in the book. The book has them using poly-juice potion and the invisibility cloak when visiting Godric's Hollow but the movie just had them walking around in the open. Even at the wedding, when Harry was poly-juiced in the book, he was just Harry in the movie. Much of his time infiltrating the Ministry of Magic was spent under the cloak but in the movie he just walked around as Runcorn.
Over all there weren't too many side-tracks or changes from the book. I guess when you have two full movies (part one is over 2 hours long) to break apart one book you should be able to do it without butchering things too much.
It ended right about where I thought it would and it set us up for a spectacular part 2. I must say for someone who wasn't all that jazzed about the series when it first came out, it has certainly lived up to the hype. I can't wait to see Harry standing over you-know-who with both wands in his hands.