Blog spammers have sunk to new lows.
Nivi, a blog I’m subscribed to, was showing dozens and dozens of entries being updated even though there was no discernible difference. However as I started looking closer, I noticed if you view the source, for example on this post, there is are ton of spam links there. You can click the screenshot to the left.
The implications of this are disturbing. His blog was hacked (which isn’t unusual and could have been for a thousand reasons like another account on his server being hacked, and old version of phpBB or other software) but instead of doing anything obvious to disturb the content of the site they invisibly modified his posts using CSS-hidden text. He has probably had hundreds of posts modified. I can’t imagine cleaning it up will be pleasant.