Well, I've just got back from seeing Immortals at my local cinema, and, unlike the other reviewers (so far)...I loved it! The movie is basically a mash-up of 'Clash Of The Titans' and '300' (it even climaxes with our heroes defending a narrow pass from a huge army). There's plenty of slow-mo battle action, but on top of that there are several scenes when the gods descend from Mt Olympus to kick villain butt, including a fantastic climactic battle between Zeus and his fellow Olympians and the newly-freed Titans. If you enjoyed '300' you'll love these scenes as the fighting is brutal. I was surprised at how violent the film was. I thought I spotted one obvious cut (when Hyperion kills Cassander) and after checking the BBFC website it seems that the film was cut by 18 seconds to get a '15' certificate'. The BBFC website also states that 'An uncut 18 classification was available', so maybe we'll get an uncut version on Blu-Ray. The director, Tarsem, is famous for his visuals (he directed 'The Cell' and 'The Fall') and the film looks great, and after seeing Henry Cavill in action I can see why he has been cast as Superman. He actually bears quite a resemblance to Christopher Reeves. The 3D in the film seemed designed to create depth of field rather than shove things in your face, so I don't think you'll really be missing anything if you only see it in 2D. I've read that the movie studios think that audiences are too sophisticated to want to see gimmicky 3D, but frankly, if I'm paying extra to see a movie in that extra D, I expect more bangs for my buck (and more things whizzing out of the screen and over my head)!
If you accept Immortals for what it is-a fun 'popcorn' movie-you'll have a great time watching it. Hopefully it will do well, as the ending clearly sets up a possible sequel, which promises more of a focus on the war between the Gods, which could be epic.