I've been working with Superfish for a little while now and I noticed some unusual behavior when I use the back button in IE7. Using the example.html in the download I set up the top level links to go to an actual html page (doesn't matter what, i.e. http://www.google.com). If I follow the first link and then hit IE7's 'back' button, the menu reloads except the first menu item is selected with it's dropdown already displayed. Also, when I highlight any other of the menu items, that first menu item stays highlighted (although the first menu's dropdown disappears).
If I follow the 2nd, 3rd or 4th and then hit IE7's 'back' button, the menu reloads exactly as if the whole page had reloaded. It can also happen in other circumstances, but I haven't really been able to isolate what's going on since I'm just beginning with jQuery.