As expected, the effort to tax bonuses at a 90% rate is meeting opposition in the Senate. Two issues are at work here, both procedural in nature.
First, the minority in the Senate has more influence than it does in the House, so is better able to say no to proposed legislation. This doesn't mean they can set the agenda, they are simply better able to thwart things they do not like.
Second, the Senate takes its time. The process is more open ended and can be slowed down long enough for rage to subside. The very fact that legislation passed by the House has to go to a second institution contributes to this.
Is this good or bad for public policy? If you believe that the current the focus on AIG bonuses takes attention from more serious problems then you probably think it its good. My hunch is that the Constitution's authors would agree.