I bought a Diamondback off the EE about 2 years ago(see one of the above posts),and I havent seen one since!
They(along with Pythons),have become quite outrageously priced since then.Because you dont see many of them for sale in Canada,I follow the US sites,and a Diamondback shown in those photos of yours,would easily go for 1200-1400.Despite the recession there,they seem to be going for quite a premium,and they dont seem to be getting any cheaper.
I find it interesting one of the above posters with his comments about a friends Diamondback and its accuracy problems.The diamondback that I bought also had some accuracy issues,until I figured out that it was really ammo specific,more so than any other 22 that Ive owned,and the throat needed a really good clean,and since then,no problems at all.Its a really lovely gun to shoot.I do shoot my Model 17s far more however,as parts and people who know what they are doing working on Colt revolvers are pretty non-existent.I still think that the Diamondback has the Smith beat on looks though!