AFAIK Buffet would support a bailout that involved buying assets at fair market value because he thinks the government could make a lot of money. He said that not buying at market value and instead giving the banks whatever they ask for these assets will likely lead to a wasted 700b. So at least in theory he supports doing the right thing.

I don't know anything about his involvement with Goldman, but maybe he realized the government will do the wrong thing anyway so he might as well profit from it.