Here's a new build that will become the official release shortly. It fixes a couple more synchronization edge cases.
Thank you all for your help in testing MM 4.1--we hope that you find the end result worth the effort!
Just double-click the downloaded file, to install MediaMonkey 4.1 on top of your existing installation.
-The MediaMonkey Team
EDIT: The build number was changed from 1691 to 1692 due to a single regression that was fixed in 1692:http://www.ventismedia.com/mantis/view.php?id=11828
p.s. Note that the beta forum will be closed until the next round of beta testing begins.