Stu Rothenberg had this to say over at Political Wire:
National and district-level numbers continue to raise red flags for Republicans around the country. In past cycles, the question was whether Democrats could nationalize races and pick off enough Republican seats to get to 218 seats -- and a majority. Now, the environment has already been nationalized and the question is whether Republicans can localize elections in enough districts to hold onto the House. It is far from clear that they can.
Given that, as I wrote in the most recent edition of the Rothenberg Political Report, we are increasing our estimate of likely Democratic gains from 7-10 seats to 8-12 seats (they need to net 15 seats for control), with a bias toward even greater Democratic gains.