Fairly hot off the presses, we have the National Labor Relations Board's decision in D.R. Horton, Inc. The decision addresses, among other things, whether a mandatory arbitration agreement that bars class or collective actions violates certain employee rights under the National Labor Relations Act. Hint: it does. Very important for certain wage & hour cases.
Full disclosure: I contributed an amicus brief in response to the NLRB's invitation for such briefs, as noted in footnote 1.