Just noticed a minor issue in 6.1 with Favorites and Links buttons from the Navigate tab not working.
To fix that, simply go to the “core” database and clear our the “command” field for both items:
/sitecore/content/Applications/Content Editor/Ribbons/Chunks/Navigate/Links /sitecore/content/Applications/Content Editor/Ribbons/Chunks/Navigate/Favorites

Good that everything is so (re)configurable in Sitecore ;-)