The only misbehavior I have noticed on my 11.1 xfce rc (dist-upgraded) is the "suspend" mode. When I select it from the "action" button/logout window on the panel, often it will suspend but immediately wake up again without being asked. If I repeat the selection immediately it will generally suspend properly until I press the start button again. Not a deal-breaker but vexing when in a hurry.
I am not sure if this occurs if pm-suspend is invoked from the CLI. This does not occur on my other linux partition, a squeeze-xfce distro. I will try to use the CLI version for a bit to see if it happens there as well.
Edit: It happens with the CLI as well...just did it.