over a year ago:
You can think of becoming a fan of a particular piece of content as the same as giving it 4 or 5 stars on the old rating system. If you don't like the content, then don't fan it. This simpler system should make it easier for people to tell others they like something without having to think about if it's worth 4 stars or 5 stars (everyone seems to choose 5 stars anyway).
If a piece of content doesn't belong in a club or is inappropriate, flagging or reporting the content is the correct action - in the past, rating it low will tend to push the content down, but won't alert anyone to take a look and remove it if inappropriate. Hopefully, we've streamlined it without creating confusion between the two tools - report if something is wrong, fan it if you like it.
I think after a little bit of time, you'll all agree that this is a quicker, easier, and better way to "rate" content.