Polls close at 10pm UTC or 5pm EDT (for me). Should know about an hour or so later?
Pretty awesome that polls stay open till 10pm in the UK. That would make it much easier to vote for people who have to work and care for kids, etc...
There won't be a definitive result until 7am BST. Apparently the final result must be available well before the London markets open at 8am BST. Various regions will announce their counts through the night.