We saw the 3D version and for this film it was really well done. It was shot in 3D from the outset unlike some films where it is added in post production, and it does for me make a huge difference. By no means over the top with the 3D, it really helped to draw you in and in places was absolutely stunning.
If you enjoyed Alien (the first one) you are bound to love this.
Also, our cinema now sells clip on 3D glasses for us speccies. They're a huge improvement over wearing two pairs of glasses.