Looks like a fairly good system, but we need more information. Look at the format in the sticky *How to ask for new build advice* to get the best help. Also, use the Samsung F3 Spinpoint 500GB instead of the WD Black for your boot drive as it will be faster than the WD Cav Black.
The Cooler Master Silent Pro 600W I've read isn't very happy when asked to crossfire, it will do it, but maybe you should think about getting another PSU. I'd recommend the OCZ ModXStream Pro 700W, as it is cheaper (if you are using newegg.com), modular, 80plus, and generally better.