I will freely admit that I haven't seen the original movie, but I've read the play, so I've some background with the "original." If you shuck off the fact that this is a remake of an old classic, this movie is smart, witty, fresh, and hilarious. Yes, the casting decisions may seem strange, but they WORK.
I'm a staunch feminist, and I wasn't offended in the slightest by this movie--despite what other women might be saying. This is NOT a movie for men to see (so please, ladies, don't drag your guys to see it with you, that's just cruel); women will get the jokes, the situations, and the relationships.
I was pleasantly surprised by the depth that Annette Bening brought to her character...she did an excellent job. Debra Messing was adorable, and Candice Bergen was fantastic. I was less impressed by Meg Ryan...she brought emotion to the table, but her comedic take on it was less strong. The all-female cast is strong, and it definitely a laugh-out-loud sort of comedy. I thoroughly enjoyed this movie, and fully intend to go see it again with my mother. Women will understand.