Exactly. Many (or shall I say most) people don't have the time to figure this out, especially across social networks. So, if it's reasonably priced it'd be definitely worth it, for example before a VC meeting ;).

I believe there is a service which allows you to search and find common interested with the person you're meeting, but this to me is more interesting.

If anyone wants to build this, feel free to ping me, would be happy to give feedback as well as sign up as a beta customer.