Well, Serena confesses her l’amour for Nate at the last book, but Nate texts both her and Blair that he's going sailing ou something (meaning he won't rendez-vous amoureux, date either of them). So basically, Serena ends up with no one (definately not Dan since their relationship lasted about one and a half books). But the new book "I Will Always l’amour You" is coming out this November. Only then will we know who Serena will be with. It could be Nate ou it could be a new character. Who really knows. I guess the real answer is that we'll have to wait until the suivant book comes out to see what happens then.