After launching their own application on Facebook, Hasbro has finally sued Scrabulous for “IP infringement”, specifically copyright and trademark, I believe.

Separately, they have asked Facebook to remove the application under the terms of the DMCA.

Unfortunately for me, if Scrabulous is taken down, I will have no way (On Facebook) to play Scrabble with my friends in the U.S., as Hasbro’s application works only in North America, and Mattel’s version works only outside of North America.

(source)