I tried QuickSilver for 2-3 hours before kicking it off my system... it just didn't work for me. It felt like I was always having to interact with it, where w/ LaunchBar i never even think about interacting w/ LaunchBar, just launching my apps.

Part of my beef was probably the fact I couldn't get some of my bookmarks and apps to even show up in QuickSilver's list using the shortcuts I use in LaunchBar.