My working paper The age of turbulence – credit derivatives style is now about to be published (forthcoming in Global Business and Finance Review). It can be found on the S-WoPEc web page here. In this paper I focus on the extreme behavior of the credit default swap market during the crisis (see the figure). The number of extreme price changes in the time period 2007-2010 is truly extreme and so is the size of the most extreme of these extremes...
As a result, anyone who wants to model the time series properties of credit default swaps in the future will run into trouble due to the structural break in June 2007. Before the crisis, the pre-crisis regime, the market was as tranquil as it was volatile in the later crisis regime. The problem is of course particularly critical since the history of the credit derivatives universe is split quite equally between the tranquil and the volatile regime; as you are well aware of, the market has only existed in ten years or so. In other words, you cannot just sweep the crisis years under the carpet! This is of course a problem not only for researchers but also for risk managers in banks and hedge funds that trade in credit derivatives. Good Luck!