Critical
Microsoft's not in the habit of issuing out-of-band security bulletins, in fact it's thought this is only the second one ever, so when it does it's probably pretty important.
There isn't much detail on offer right now apart from what you can see on the screenshot of the bulletin announcement below, that it concerns Windows, is of critical (highest) importance and addresses a remote code execution vulnerability.
Thanks to HEXUS.community member Moby-Dick for bringing this to our attention. We'll bring you more details as we receive them.
Update, 18:00, 23rd October 2008: The Microsoft bulletin page has now been updated with a bit more information. Click here to access it.
