Really good through the first part. It went to shit about half way through. Something about the Amphibious cars driving over 70' waterfalls and not losing their passengers just really bugged me.
By the end of the movie, It was obvious that the "alien" plot and bad CGI had become the base building block of the last half of the movie. They completely lost touch with the older movies, IMO. I wouldn't watch it again.
I should have just stuck to the original plan and watched The Chronicles Of Narnia.