The AdWords account interface is temporarily unavailable due to system maintenance. AdWords is expected to be down from approximately 10:00 AM until 2:00 PM PST [?] on March 8, 2008. Please note that your campaigns will be running normally during this short period of downtime, which only affects your account management pages. We apologise for any inconvenience. this is what I got when just trying to log in
I meant they put a notice at the top when you login that says exactly when the system will be down - so you can manage your campaigns around that time.