If you want to a have a virgin New Moon experience when you go to see the movie, stop reading now because I'm going to spew out all my thoughts without filtering for potential spoilers.
Last chance to back out.
The sparkle factor is still majorly underwhelming. I mean, come on. A major plot point revolves around Edward stepping out into the sunlight, sans t-shirt to show off his glittering body, which will reveal the existence of vampires to the world. Ignoring how stupid that is - in a world where this can be seen in every major city no one's going to give a sparkling man a second glance - whenever a vampire steps into the sunlight he just looks a little sweaty. If you're gonna sparkle, I want a friggin' disco ball effect, not something that could be covered up with a little bit of foundation powder.
I still think Kristen Stewart is an AWFUL actress. Her voice just bothers me, always so hoarse and flat and rather boyish, but considering what a piece of blah work that Bella is maybe Stewart's secretly a genius and capturing the character perfectly.
They did a better job with make-up than in the first movie. Edward's white skin still looks incredibly fake, but at least he doesn't have obvious make-up lines at the neck all the time. I think Robert Pattison, as dreamboat vampire Edward Cullen, has not managed to string together a single coherent sentence in these movies. Even the most basic comments are filled with awkward pauses and are strung out for maximum non-effect. I know my coworkers are just mad about Edward, but I think he's:
A/ A creep.
C/ Manipulative bastard
D/ Weird-looking (His huge forehead makes him look like a caveman)
E/ Distant, unemotive, and freakin' WHINY
F/ Also, an unrealistic prude.
So with the two main actors sucking it hard, I thought it was going to be a loooooong movie. And it was. New Moon has some serious pacing issues if you ask me. Maybe it's just a consequence of seeing the movie at 12:01 am (although it didn't actually start 'til well after 12:30 once you factor in delays and previews) but the first 1/2 hour reeeeeally dragged and the last 45 minutes draaaaaaaaagged even more. But most of the secondary, background characters are really, really well done. Characters like Jessica, Charlie, and Billy Black are given far more development than they got in the book just through the nuances of the actors' performances, while many of the vampires - Laurent, Jasper, Alice - are actually cool. (OK, Alice was cool in the novel, but I literally remember nothing about Jasper from that book.)
I refuse to declare myself Team anything, but I definitely sympathize with Jacob in this book and this movie. He just gets a horribly raw deal all around. He's obviously crushing on Bella since Day One (WHY? SHE HAS NO APPEALING TRAITS WHATSOEVER) and bending over backwards to please her, and she just brushes him off whenever the thought of Edward crosses her mind. How tragic for him. The kid playing Jacob (Taylor something?) did a really great job. I love that he doesn't feel the need to fill scenes with awkward mouth breathign like his costars. But at the end, I liked the character and wanted him to get the girl, even though she's no prize. (I really don't like Bella. Have you noticed?) Even when he's pulling total douchebag moves (telling Edward Charlie's planning a funeral, for example) Jacob is so much more...well, human than Mr. Cullen.
It's pretty cool that the Native American characters are actually played by people of Indian descent. Rock on, casting.
I don't remember the 'Dear Alice' device that Bella was constantly using from the book. Was it in there? I didn't bother to re-read before seeing the film, so most major details/omissions went unnoticed by me.
One last moment of Bella/Kristen Stewart hating before I stop: Her nightmare screams? TOTALLY LAME AND ANNOYING.
Edit to add: How did I forget Alice's vision of Bella becoming a vampire at the end? IT'S LITERALLY THIRTY SECONDS OF EDWARD AND BELLA RUNNING THROUGH THE WOODS, SPARKLING/SWEATING, and was probably the most inappropriate/unintentionally hilarious scene ever. Frolicing in the woods in sundresses! As vampires! It was horrible.
Edit 2: The constant shirtlessness of the men, and actually just a lot of the lighting and general camera work made me think of old Backstreet Boys music videos, specifically the one where they're all running around in the rain. It's like, chaste gay porn. Without the sex. Obviously. Or something.