MT 2.61 important update
This just in via the MT-Users mailing list...
Due to a vulnerability that's been discovered in the file Author.pm, it's imperative that any installation of 2.6 be upgraded immediately.
Download the new Author.pm file here:
http://www.movabletype.org/downloads/Author.pm
And replace the version on your server at lib/MT/Author.pm.
Note: If you have yet upgraded to 2.6, you may disregard this message and upgrade to 2.61 at any time.
If you've already upgraded to 2.61, you may still need to do this update.
Update: This vulnerability patch was significant enough to warrant a minor point release. Upgrade to MT 2.62 if you have MT 2.6 or later installed.
This was indeed probably the worst, scariest vulnerability there ever was. I had a bit of a 'mare when I realised what it was! I've never taken a website down so fast in my life.