In the State of the City Adress, Mayor Bing mentioned how light rail construction will start no later than 2012. I don't really have much background information on how rail-based transit sytems are built or planned, nor do i know how Detroit handles such matters, my hypothetical question is, IF light rail construction in fact would start sometime in 2012, how long do any of you think it would take to build the first stretch from Hart Plaza to New Center to where it would be in full operation? Just an estimation obviously