Actually I find spotlight barely usable. Granted, I'm on an older Apple machine, but for me Quicksilver is the way to go hands down. Personally, I wish that Apple got rid of spotlight years ago, purchased Quicksilver, and integrated it into their base operating system. Cmd+space or ctrl+space for quick launch of applications, folders, contacts, sending email, doing arithmetic, looking up words, sending an instant message, running an applescript, and practically anything else that you would want to do on your system.
I wouldn't say the dock is useless, but over the past six years I've probably used it for less than 1% of the applications that I launch.