ROFLMAO. This movie had some purely hilarious moments--and was generally funny all the way through. I have of course read the book, and I think the movie was fairly faithful to Dave Barry's stream of consciousness style of writing and his at times outrageous sense of comedy. If you haven't read his work, you should do so, as the movie was faithful enough to the style that you could find yourself getting lost in the lack of structure and the odd, almost random, flow of the film. If you HAVE read this book and his other works--then definitely see this movie. The casting was superb, the cinematography was very good, and there was a high level of natural chemistry between the actors that worked very well. If you're looking for refined humor, or outright slapstick, then this wouldn't be your first choice. If, however, you appreciate the sheer slings and arrows of outrageous bourbon (or fortune, as the case may be) where "truth" really is far stranger than "fiction"--you'll like this.
You'll especially like this if you are one of those people who is a nexxus for the improbable. The whole plot and premise range from slightly improbable to absolutely impossible--but it works, as does the typical life.