I have to admit this is a very big subject, and I'm not an expert on Canada, so I'll talk from the European perspective--and also as somebody who wasn't there from the launch of the EU ETS, in the job sense.
The major lesson for us is simplicity. The EU ETS is a relatively simple scheme. You talked about apples versus apples compared to apples versus oranges. We have one common currency, which is a metric tonne of CO2, and that's very important. Then what we have is an absolute emissions reduction commitment, which at the moment is made up of additions of the 27 member states caps, to have an overall EU cap.
One of the lessons, in terms of simplicity, and one of the lessons we're taking forward to post-2012--so from 2013 onwards--is to have the cap set as far as possible at the EU level, because one of the complications is allocation of allowances. Once you have a scheme up and running there's a lot of money at stake, and that leads to very difficult decisions for whoever is making the decisions, whether it be, in the EU context, the commission looking at national allocation plans or people developing national allocation plans and deciding on what to allocate to different installations within their countries.
The more that can be simplified and the more it's within the confines of what's being done elsewhere in the world, so that the competitive impact on the companies that are exposed to international competition.... The more those allowances can be sold--not allocated, but sold--say, through auction, the easier it will be. So that's an important lesson.
I'll hand it over to James. From a member state perspective, he may have other lessons he wants to raise.