Do you know of somewhere on the web that posts unit sales of dSLRs? I've always been curious.
No one publishes accurate sales by model of DSLR's, those sites out there merely get a small amount of data and extrapolate it, which can be extremely inaccurate.
Amazon sells a large number of cameras, and they have a sort of rolling best sellers list, which gives you a idea of what is popular, but, since i don't know exactly how it is computed, take it with a grain of salt. For example, the D7000 is listed high on the list, so they must be counting pre-orders as sales, because they are and have been out of stock or short on stock.