My preference is on the left-hand side of my 16:9 MacBook Pro screen. I keep only essential icons there (it's so easy to get to LaunchPad for any less-used apps), and it just feels like the right place for a widescreen display.
Seeing how I just came from PC and am used to having the taskbar on the bottom, I also prefer having the dock on the bottom as well. I also have it set to auto hide so I can have more room!