Not logoff or restart. But under the advanced power setting you can
configure the power button to power off the computer. It changes
colour from yellowish to red to differentiate the action. I'd like to
have a restart button too. Another step backwards for Vista.
And that's another thing that bothers me about the start menu. The
sleep button is actually a power off icon, so it's misleading in its
default configuration.
I don't know about you, but I don't have a suspend button. I have a "Saves
your session and puts your computer in a low-power state so that you can
quickly resume your work." button.