Quick feedback: when you change the filtering on the left hand nav, you scroll to the top of the page. I really don't need to see the huge masthead (on my small Macbook Air, in Chrome, the masthead is over 2/3 of my vertical screen) again on every click. Just scroll to the top of the list/filter section, not the top of the page.

I see... it was hidden in that dinky greyed out button that needed to be clicked. I hope your UX is not inspired from Windows 8 ;).