Dude, I just found out that Matthew Macfadyen was born in 1974. That means he was about 30 when he filmed Pride and Prejudice in 2004. Whereas Keira Knightley was 19. Mike guessed that he was 24 before I looked it up. I find this weird because I get a very young and well-matched vibe off of the two in in the movie, so I never would have guessed. To compare, there is about a 9 year age difference between Colin Firth and Jennifer Ehle. When the A and E series was released (I don't know exactly when it was filmed), Firth was about 35 and Ehle was about 26. I believe that Lizzie is supposed to be 20 (I think she turns 21 during the course of the novel), and Darcy is supposed to be in his mid-twenties.
So I guess Keira was really pulling her weight in giving the newer version that young freshness.
Oh, and in case you were wondering, I did go out and buy the Pride and Prejudice DVD this week. I watched it as soon as I got home.