they are both very different. in practise, instagram may be a good thing at creating  behind the scene albums (culture introduction) and maybe to some extent at product photography… But the target audience should be insta-friendly too. And photos should be for only social sharing needs, not for on-site photos.

Pinterest is quite well established for generating leads to e-commerce and other sites.Plus People spend their time @ pinterest, while people tend to use instagram, and not scroll their news feed that much.

For me, more of my potential clients are on Pinterest than Instagram so it’s not a big decision.  But I agree with Tomas that I think Pinterest is a more sticky site so it might be generally better for marketing.

As a marketing professional, I use Instagram because it allows multiple people in my office to log into the same account and post pictures from client events we are covering.Instagram can be used as a real time picture network similar to Twitter as Pinterest is more like Facebook in that pictures have a longer shelf life and can be posted after the fact.Hope this helps.

@geoffrey-gordon

Nice list!