As someone who read the books first, I can't imagine how random it must feel when Bill just waltzes on into the Dursley's home in DH Pt. 1 and he and Fleur Delacour from way back in GoF are engaged and about to marry.
No explanation like in the books either. No "we met while back in during the Third Triwizard Task, then she took a part-time job at Gringotts to better her English---and now we are in love and going to get married!".