All in One SEO, WP Super Cache, WP Download Monitor, Magic Members, PayPal button WordPress 3.2 theme twenty ten 1.2 based theme.
Adsense and the like code is inserted via shortcodes and I have not noticed this before.
This problem is only in the header of type posts, and I have your plugin set for posts only, script loaded in the footer, so it is strange it is picking the text up, as the header is generated before the footer.
If I add a description in the all in one SEO fields, I do not get the funny html, but I would rather not do this for over 100 posts.
I tried the automatic upgrade today and got the same error, all files deleted except the includes directory, I did not upload all files via ftp as that is what locked me out before.
I tried to delete the /includes/ folder, this would not delete for about ten minutes.
Within the ten minutes I tried to overwrite just the includes folder and got a message about one of the files not being readable, this looks like the file that has caused the problem, it is the one that has the access to the api, might be held open or some other comms issue when updating.