With the new Windows Vista Start menu, the keyboard shortcuts have once again been reorganized. You used to be able to hit the Windows key and then type L to call up the Log off menu, and then L again to trigger the logoff. Or you can hit the Windows key and then type I to launch Internet Explorer if you've been so careful to ensure that Internet Explorer is the only program that you run frequently which begins with the letter I. With Windows Vista, the keyboard focus is on the Search box when you open the Start menu, so these one-letter shortcuts are treated as the start of a search.
The designers of the Windows Vista Start menu realized that the loss of these one-letter shortcuts was a drawback of the new design. Their rationale for the change was that they were providing quick two- or three-letter shortcuts to hundreds of programs and documents that users frequently use, at a cost of one-letter shortcuts to a very small number of programs.
But all is not lost. The Search box still knows about what you do most often. If you really log off that frequently, then when you type L, the option to Log off will be at the top of the search hits, and you can just hit Enter to confirm.
Windows, L, L is now Windows, L, Enter. Same number of keystrokes, but now more flexible and adaptive.