Congress' Approval Rating Lowest in 30 Years

Congress' approval rating has hit 30-year low according to Gallup. Is it because of the economy, the way President Obama is handling it, because they're in a lame-duck session, Democrat infighting or simply because people no longer trust the Democrats? An over-the-rainbow explanation could also be that even though the Republicans haven't officially taken over the House, maybe people don't trust them either and are showing it early. Of course that wouldn't really explain a 60-seat gain last month. It's just a thought.