Summit Entertainment

Twilight's going to keep a lot of people up all night.

Across the country, more than 1,100 midnight Friday screenings were reported sold out. In Los Angeles, pairs of tickets were hawked for upwards of $50 on Craigslist. On Facebook, members were planning their opening-night wardrobe.

Suffice to say, Team Edward T-shirts—and the fans wearing them—will be out in force.

"I think the opening day is going to be huge," says Bruce Nash of the box-office data site, the Numbers.

But how huge? That's a trickier answer.

"There are certain movies that are hard to gauge," says box-office analyst Paul Dergarabedian of Media by Numbers. "This is a weird one."

While there's no shortage of buzz about the stars, led by the lion-maned Robert Pattinson, and no shortage of book sales for the Stephenie Meyer series on which the film's based, there's also no box-office precedent for a gothic vampire flick aimed at teenage girls.

"We haven't seen a movie for this specific demographic ever," says Jeff Bock of the tracking firm Exhibitor Relations.

Projections, accordingly, vary. On the plus side for Summit Entertainment, the indie studio looking for its breakthrough blockbuster, they're varying on the high side. Especially for a movie made for a Hollywood-modest $37 million.

Dergarabedian thinks a $30-40 million Friday-Sunday debut is possible. Bock wouldn't be surprised by an opening of $30 million—or $70 million. Nash sits in the middle, calling for a $60 million-ish debut.

None of this means Bolt won't reassert the talking-dog movie's dominance, and open No. 1. None of this means Twilight will make like High School Musical 3: Senior Year, and keep filling seats after this weekend.

All this means is nobody knows anything for sure, except for maybe this: Twilight's highlight is going to come early.

Nearly 600 Friday midnight screenings were reported sold out as of Wednesday by the ticket service Fandango. Just under 550 were reported cleaned out as of today by MovieTickets.com. (Fandango and E! Online are both owned by Comcast.)

Overall, box-office watchers say some 2,000 opening-day screenings are already booked.

Nash isn't expecting Twilight to pull a Dark Knight, which bolted out of the gate with a record-smashing $67.2 million opening day in July, but he's not ruling out a debut along the hemlines of Sex and the City, which opened eyes with a $26.7 million Friday in May.

"I think there's a core audience that wants to see the new movie no matter what," says Nash.

And movie reviews, which haven't been overwhelmingly kind to Twilight, won't matter, says Dergabedian.

"You tell me one teen girl who's going to care a lick about a bad review," he says.

Sneak a peek at the Twilight phenomenon in our updated gallery!