Dood, don\'t tell me you don\'t see a difference of the locked and un locked taskbar?
First of all you can\'t move it until you unlock it, so no more actidental moving of quicklaunch icons, and the taskbar will stay where you want it to stay, no more actidental moving it to the side of the screen. And thos kind of things.
It\'s probly my favourite feature of WinXP