There has been a major update to the Steam Subscriber Agreement. Changes include a clause saying that all EU subscribers are no longer licencing games from Valve Corporation in the United States, but from "Valve S.a.r.l.", Valve's new office in Luxembourg. The terms of service for both EU and non-EU subscribers are mostly the same.
Most importantly for US-residents is section 12 which includes a clause saying that you waive the right to bring a class-action suit against Valve. One can still bring Valve to small claims court or through a binding arbitration process outlined in the agreement. If you are seeking $10,000 or less Valve will reimburse you the cost of the arbitration process unless the arbitrator determines that the claims were frivolous or amount of money sought unreasonable. This section is likely not legally binding to anyone living outside of the United States.
Valve is aware that these changes are, at the every least, rather controversial but has said that "We think this new dispute resolution process is faster and better for you and Valve while avoiding unnecessary costs, and that it will therefore benefit the community as a whole." Despite this assurance they have set up a feedback form for those who wish to share their thoughts or complaints regarding the policy change. You can find it here.