I watched this because I have seen the others. Not as great as the first but better than the 3rd one with the pirates. Good use of 3D with some surprises. A bit too much of Scrat in the extras. Animation is well done and plenty of laughs are in there too.
If you have skipped the other blu ray version of this, jump on the wagon and buy this one. The restoration is nicely done with nice bright colors and the right amount of red in the gore. Sound can be a bit fuzzy in some scenes but the spots are brief and it's still clear enough to be easily understood. Much better picture quality than the older restoration and the old original DVD release.
A well done film that many people missed at the theater. If you have never played the game, don't worry, the film stands on it's own. Very good CGI all through the film and good use of 3D if you get that version. CGI characters that you actually feel for and admire .. or dislike immensely. Watch the film, enjoy it and hope they make a sequel as this opens the door for one to be made.