I really don't feel that I can comment intelligently. My assessment of the situation is that both carbon taxes and cap-and-trade are attempts to internalize the externalities of emissions so either is better than neither. This is not an intelligent assessment, however, and the product of a sketchy understanding of the realities on the ground at best. I know that market forces will act quicker when there is money to be made.
That's my impression as well. I think if the US and China (plus maybe Europe or Russia or a smattering of other large developed/developing economies) could come to a big enough agreement about carbon pricing, the smaller economies would get swept along with the global market. It will be interesting to see what comes out of COP 21 this year.