I watched this tonight, on DVD. I am a huge fan of the book, and was expecting to hate it. I thought Matthew McFaddyn was lovely as Darcy, and even Keira excelled herself. I don't think that she is a great actress, but I liked her as Lizzie (Certainly more than Jennifer Ehle!)
They changed bits, and left bits out (of course, as the book is too long to include everything in 2 hours), but it kept the essence of Austen's love story. Hated the US alternative ending though...scmaltzy and insulting to the viewers.