The movie is going to be a hit no matter what, but her is what critics and users feel:

Yahoo! Movies
Critic’s Average Grade: C+
Yahoo! Users Average Grade: B

Rotten Tomatoes
T-Meter Critics: 44% or Rotten
Top Critics: 55% or Rotten
Rotten Tomato Community: 36% or Rotten

“Not that Twilight’s fate hangs on intelligibility. It hangs on fangs that aren’t bared, and on a bloodlust that isn’t indulged.” – Joe Morgenstern (Wall Street Journal)

“Twilight works as both love story and vampire story, thanks mainly to the performances of its principals.” – Michael O’Sullivan (Washington Post)

“…It’s a fleeting reminder of how much dumb fun is missing from this oddly neutered neo-horror movie, and how little is being offered in its place. In “Twilight,” the only characters drained dry are the vampires themselves.” – Kurt Loder (MTV)

“My advice: Focus on Pattinson and Stewart. They make you understand why the books sold 17 million copies.” – Peter Travers (Rolling Stone)

“Combines the plot of HBO’s True Blood with the intensity level of Saved by the Bell.” – Kyle Smith (New York Post)