If you go to http://www.vfdaily.com/culture/2008/blogopticon/index.html and open any of the links from the context menu, the little pop-up associated with the icon stays up, even if the mouse is moved over a different icon. "Select tabs and windows as they are created" is not checked in the preferences, if it makes any difference.
Works in the latest nightly, under OS X 10.6.0