I've seen a lot of people comparing Nevada turnout to 2008. Careful! Remember, context matters. Several issues...in 2008, Nevada had just moved up in the process, and so it was sort of a first-time thing, which might have increased turnout over this year. It was also essentially earlier in the process. In 2008, Nevada went on the same day as South Carolina, and before Florida -- although Michigan had squeezed in between New Hampshire and Nevada/South Carolina. Between the calendar and the way the process played out, the nomination was far more up for grabs when Nevada caucused in 2008 than it was this time around. In fact, there were still three viable candidates at that point (McCain, Huck, and Romney), and the press was still treating Fred Thompson and Giuliani as viable candidates, although they really weren't. And Ron Paul was Ron Paul.
I have no idea how to adjust for any of that, but at least in my view it's silly to do a straight year-to-year comparison without keeping the context in mind.