Plentyoffish.com is looking for a PhD to build a referral engine

Didn't chemistry.com start as a referral engine test by a PhD? (This may be heresy.)

The fact that you have PhD at the top of your list, rather than as a footnote, tells me that you don't know what you need in a designer/developer, aren't entirely sure that your concept is viable or even doable, and are likely to wind up with some mediocre corporate programmer with little experience, and even less creativity, rather than someone who truly knows what he's doing and could have turned your idea into a real product; and as is usually the case, your poor selection in a designer/developer will result in a poor company with mediocre products that probably don't work like they were originally meant to, but not before you burn all of your venture capital on his salary and numerous wasted expenses on infrastructure and partner products to give your non-working solution an overcomplicated and underrated backend.

Good luck!