At this point, the only thing stopping me from using Alfred full time is the equivalent of the "UI Access" plugin in QuickSilver. The UI access plugin in QS allowed you to search through any menu item available in the current application. You can set up a hotkey using a proxy object (current application) and quickly type in commands that's available in the menu.
I use this a lot in Photoshop, and a lot of other application where there are incredible amount of menu items that I don't feel like digging through each and every time.
There is a workflow available right now that searches through the menu bar, but the workflow is really slow. I would love to see this feature just baked into Alfred.