I've been using Windows 7 since the public beta release, now running Windows 7 Ultimate x86. In the last day or two I noticed that at some point, Explorer became unpinned from the taskbar. I re-pinned it, but noticed that Jump Lists for Explorer are not simply not displayed at all. When I right-click on Explorer's icon, I get the options to open Explorer, unpin from Taskbar, and (if a window is open), close window. Native apps which support jump lists like Notepad are still working, and I'm running the Minefield Nightly version of Firefox and that displays jumplists just fine as well. The problem is isolated to just Explorer, the main program I actually use Jump Lists on...
I have had little luck in Googling this up. I had found that some people had some issues with CCleaner causing Jump List problems. I DID actually have CCleaner installed on this machine but never really used it. Fiddling with CCleaner's jump list settings and even uninstalling it both had no effect, the issue persists.
Anyone have any hints for stuff to look at? I imagine this is as simple as a registry tweak to turn the feature back on.