Saw it today (in 2d). I give it a solid B, maybe a B-. The look was good. Had a pretty gritty western look to it. The acting was good. Nice performance from Harrison Ford, Daniel Craig, and Olivia Wilde. Olivia looks great on screen. Very pretty. Decent sound, although not a memorable sound track, but of course it's the old West so they're not going to be playing the latest rock or dubstep or anything. Special Effects looked good, and I liked the aliens.
However, I walked out going, liked it, didn't love it. Why?
Had to think a minute, and it was the same old thing. The Script. Decent, but not great, and full of holes. Also, lacked some realism. This did not feel like folks from the 1800's encountering aliens. Felt more like people from the 21st century, wearing clothes from the 1800's, encountering aliens.
I won't give away any spoilers. It's definitely worth a matinee IMO, but falls short of blockbuster material.
They decided to go for film on this one, as well as keep it 2d:
“We knew we’d have a lot of day exteriors, and I’ve always been averse to shooting digital in day exteriors,” says Libatique. “Shooting film is going to be better then trying to struggle with a format that clips in the highlights. I think some of these problems have been mitigated, but they still exist.
“The more we learned, the more we felt that 3D might hurt the film as a film,” he says. “I felt that anamorphic 35 mm would work better with the way Jon handles performance and coverage. But the main reason we came to a consensus was that anamorphic allowed us to adhere to Western cinematic language.”