I've just check my Google webmaster tools dashboard and all but one of my dozen or so sites needs verification. Now I do get an individual site requiring verification from time to time, but usually after I have uploaded a new version which doesn't contain the meta tag. However I've never seen almost all my sites require verification. Some of them haven't been touched for months - ie the meta tag could not have been removed.
I've just checked one and the meta tag is there, so I attempted a re-verification and I get the message 'We were unable to verify your file due to a server timeout.' yet I can browse to the site quite happily via a dialup connection.
Anyone else experiencing a similar issue?