In Alfred 2, I have a lot of Hotkey > Launch Apps/Files workflows, where I use global hotkeys to open/switch-between applications.
I've noticed a slight delay (~200ms) between triggering a hotkey combination (⇧^C) and its corresponding Action (showing Chrome) taking place.
I still have Alfred 1.3.3 (267) installed, and when I use that instead (making sure to not run both versions side-by-side), the delay is not there. It's much snappier.
Alfred 2.0.1 (173)
OS X 10.8.3
Aside from that, love the new Alfred