One thing to watch for is how much the Republicans applaud the President. The unified Republican opposition to the stimulus in the House and the fact that only three Republicans crossed over to vote for it in the Senate has come to define the Republicans. The plus side for them is that any problems with the stimulus, which has far too many pork barrel and poorly thought-through projects in it, work to their advantage. But the risk is that they look obstructionist at a time when the public wants, as Alex notes, cooperation.
If the nations sees them seating on their hands tonight as Obama reaches out to them it could hurt them. But then again Congressional Democrats didn’t appear to suffer much damage in 2006 for applauding themsleves for their obstructonism when Bush noted that Congress had failed to act on his plan to reform social security.