Almost all the tourist that visit Burma, visit U Bein Bridge, either as an excursion from Mandalay or what I personally prefer from Sagaing, and that is clear to see by the hoards of people that throng to and fro across the bridge.
Many people make a quick stop enroute to another excursion, however it is worth taking your time here. Walk around the lake, observe the fishing, the daily life beneath the bridge, especially at sunset when all eyes and cameras are focused on the bridge and boats full of tourist jostle to obtain the best photographic vantage point.
Walk away - there are peaceful scenes waiting to be found.