On August 25, the Washington state Democratic, Republican, and Libertarian Parties filed their rebuttal briefs in Washington State Republican Party v Washington State Grange, 11-35125. All the briefs are now in. The 9th circuit will probably hold an oral argument in this case in the next few months. This is the lawsuit, originally filed in 2005, that challenges the top-two system in Washington state. The case has been up to the U.S. Supreme Court and back down again.
Here is the Republican brief; here is the Democratic brief; here is the Libertarian brief.