It's a reference from the movie, Jerry Maguire. Sports agent Jerry (Tom Cruise) finds out that he really does dig the girl he screwed over and goes back to her house to hopefully win the girl back. She is having a man-hater party with the girls and he walks in and says, "Hello", then states how he digs her and needs her. After going on for a long time, she replies, "You had me at hello" and they dive into each others arms and are happy. So I referenced the movie, since I dig the Hemingway line, "You had me at Hemingway".
http://www.youtube.com/watch?v=AyrP-pwDayE
Sorry for the odd reference. I will go punch my man card now.