While the premise for this movie is different from the book, and the characters are made to match the premise, this movie is frenetically full of gags (and almost never loses a chance to reuse anything already introduced).
The one problem that I had with this movie is the use of scatological jokes and imagery (although except for the entrance/exit to the lab they are usually fleeting).
I laughed out loud many times, and was quite taken with the references to 'standard' disaster movies.