If you've bought a new Shimano front wheel or hub since November 2005, check the following link to see if you need to get the QR replaced.
Better safe than sorry!
[url=http://cycle.shimano-eu.com/publish/content/cycle/seh/nl/en/news___info/voluntary_recall.-MainContent-0009-DownloadFile.tmp/UK-GB.pdf.pdf]Product recall[/url]