Remove delay from OS X dock when auto hiding
If you would like to have the dock to appear / hide instantly without any delay then follow the steps below.
Step 1: Open Terminal
Step 2: Copy and paste the following command into a Terminal window:
defaults write com.apple.dock autohide -bool true && defaults write com.apple.dock autohide-delay -float 0 && defaults write com.apple.dock autohide-time-modifier -float 0 && killall Dock
To remove all of these changes, and bring back your dock, simply paste the following command into a Terminal window:
defaults delete com.apple.dock autohide && defaults delete com.apple.dock autohide-delay && defaults delete com.apple.dock autohide-time-modifier && killall Dock
See Video: http://www.youtube.com/watch?v=zfya9009hCE