There were still some kilometer markers on the roads in Alabama when I moved there in 1997. Apparently, the state spent $3.2 million to put up km markers and signs in addition to the mile markers and signs. This proved to be too confusing, and they were all taken down. Most the people I knew didn't miss them. http://news.google.com/newspapers?nid=1842&dat=19971128&...
I personally thought the kilometer signs were pretty cool. The person's comment about the metric initiative being hard to defend when none of the other states followed through seems to ring true -- it's easy to see how the public might have thought they had been talked into a boondoggle.