I just got back from a trip to New York. Some friends and I went hon-ya (japanese for bookstore) hopping. I found out that Hojo Tsukasa (City Hunter and Cats Eye) has come out with a new series. It's called Angel Heart
It takes place in the City Hunter world. It is some time later, and Kaori has died in a car accident. Her heart has been transplanted into a young woman who is a trained assassin. But because her heart is Kaori's she starts having emotional conflicts about her vocation. She manages to escape from the group she's in, and finds her way to City Hunter territory, where Ryo is still acting as usual. The interesting thing is that Ryo in this series seems much more serious, and he has not given up on finding Kaori. He still insists that she is alive somewhere and he will find her.
Tsukasa-sensei has done a really nice job on this series, from what I've seen. While keeping the same style that he had with the City Hunter series, the characters from that series all look subtly older. I believe that Umibouzu is now completely blind. And Ryo's hair is thinned out, and his skin is tighter.
Anyway, if anyone has a chance to get this one, and has seen any of Tsukasa-sensei's previous works, I recommend you look into this series.