It seems that the official release of Vista already has a bug, or bugs, that seriously hinder the ability of a user to keep their system up and running more than 1 day at a time or even allow you to allow the system to go into Deep Sleep or hibernation.
I don't know about most of you, but my computers are rarely shut down or rebooted, and when not in use go into a hibernation state. Well, this is not really possible with Vista. If you put it into Deep Sleep or hibernation a multitude of things can/will happen. All of them will require you to reboot, but one is serious enough that you cannot use rebooting to fix it unless you use the installation dvd to recover from the problem. Even Safe Mode will not work to recover from the system errors.
According to the author MS does not know the exact cause of many of these problems--the author has reported the bugs to MS and has gotten feedback from them--and the author is pointing at the Vista Kernel and/or a broken ACPI model as likely culprits for some of them. The author also says that some of these will not be easy to fix.
Take a look at this blog post
from a blog called "The Neosmart Files" to read the exact details.