We flew on a BA 777 to New York a couple of years ago and dh (who's 6'3") felt that the legroom was slightly better than Virgin 747-400s. Could have been just his perception I guess as the cabin definitely has a more spacious feel to it (something to do with the way the overhead lockers are situated, I felt), and the seats had some clever headrests and bigger than normal seatback tv screens.