Apparently Google in Japan got a big penalty placed on them by Google themselves, taking their toolbar PageRank level from 9 to 5 (Search Engine Land posted an update about this on an earlier story they had). This is a huge sign – one, that Google takes bad actions by any site (even themselves) very seriously.
Only now has the penalty been removed, although the toolbar PageRank is only up to 8 (not 9). That’s almost a full year of penalization (11 months, to be precise).
The malady that Google Japan performed? They paid bloggers to review a new Google widget. This isn’t the first time Google instated a penalty on themselves – it does go to show that Google enforces their rules consistently, even against themselves.
It demonstrates that if you want to be sure to keep good rankings, you do have to follow Google’s Webmaster Guidelines.