A guy named Neil has taken down his Android game with the same game play as Settlers of Catan after facing a legal threat from Catan GmbH. (source)

The legal threat explicitly notes that game rules cannot be copyrighted, but, since the game of Catan also embodies a storyline (“Players are recent immigrants to the newly populated island of Catan.”), the associated game play thus becomes copyrightable.

I’m not a lawyer, but this appears to me to be entirely bogus (see why), but as usual the little guy is in no position to take it to court. And the real reason for the letter seems to be that Catan will be releasing their own Android app. (source)