D.C.
Whenever you switch over to milk and cups, just trade that bedtime bottle for a cup of milk. That's what I did with my daughter (and am doing with my son now) and it's worked well for us. We stopped using the bottle by 12 months for both. (My son is 11 months now and we're in the process of switching...hopefully we'll be done by his birthday next week.) I think the longer you keep using the bottle, the more attached they become...toddlers are tougher as they get older and more opinionated.
Good luck.