Provide visual indicator when filtering/sorting
When I click filter or sort, there is no visual indicator the page is working - no page load progress bar, spining "page is loading" indicator in the firefox tab, and no visual cue on the webpage. The sort is not instant, so I sit there wondering if I actually clicked the button. Then I blink, and my stuff is filtered or in a different order.
See the appexchange for an example of this - when you narrow your search, a tiny "refreshing results" appears - not great, but at least I know it's working.
