To the best of my knowledge, it makes no sense.
You can't duplicate content, because Google will penalise you. Having 2 separate identities makes little sense unless they're 2 separate businesses. The best thing to do with the domain name from what I've read is to put a permanent redirect on it (that or put up a flash slideshow with a link direct to your current site.
In your shoes, I'd spend the money on a Pro Photo wordpress template (to replace your current site), not cheap but they make everything else simple. There may be other premium templates that'd do the job as well, but the nature of feedback and testing means that for me I'd rather go to the one place I know will work.