He's been shut out of Thursday's Game 4 between the Caps and Boston Bruins at Verizon Center as a result of his cross-check to the face of Rich Peverley after Game 3, and the team released a statement on Wednesday voicing their displeasure with the NHL's decision to uphold that ban.
Via the Caps, the full statement:
We disagree with the NHL's decision to suspend Nicklas Backstrom. This has been a competitive and physical series, and we do not understand why a suspension was imposed in this case while other incidents in this series have not been reviewed. Our singular focus now is on Game 4, and we look forward to the energy that our great fans provide.
Meanwhile, Backstrom himself says that the play was "stupid on my part." That doesn't mean he agrees with the suspension either, but it does mean he takes responsibility for being ... well, stupid.