"Pelosi threatens discharge petition to force vote on middle-income tax cut extension."
— @brianbeutler via Janetter for Mac

So what does that mean? There's a bill, passed by the Senate way back in July, to extend just the tax cuts for the middle class. House Speaker Boehner has refused to bring this bill to the floor of the House. So Pelosi is mulling an effort to force leadership to take up that bill, which President Obama is ready to sign.

It's not going to be easy to achieve, because she needs 218 signatures for the petition to work, and that means getting 25 Republicans on board.

Here's a link to info on the bill the Senate passed in July: S.3412 The Middle Class Tax Cut Act.