If you go to LaunchPad, you can search for apps by typing a couple of letters. You'll see a search field at the top of the window. You don't need to move the cursor there; you just start typing. Launchpad will narrow down its list of apps to those named with the same initial characters as any typed text. For example, "pre" will return Preview, whereas "rev" won't.
Additionally, it returns apps that contain capital letters and words' initial letters from any consecutive position within their names that match the typed text. So, "qt" will return QuickTime Player, "sp" will return System Preferences, and "p" will return iPhoto.
[kirkmc adds: It seems that LaunchPad treats capital letters at any location in an application name as important, just as Spotlight does.]
Mac OS X Hints
http://hints.macworld.com/article.php?story=20120804033439685