FYI, here is a summary of the year 2000 draft plan to reduce crowding in Yosemite Valley. I don't know the current status of this plan. My wife and I went into the Valley last October, and saw that the big parking lot at the Yosemite Falls area has been removed. Does anyone know what else has been done?
http://home.nps.gov/news/release.htm?id=24P.S. Here is the link to Yosemite projects as of 2010, including Half Dome rehab:
http://parkplanning.nps.gov/parkHome.cfm?parkID=347