I see this kind of language quite a bit in contracts and licenses I look at before passing it along to our legal team here at the university ... essentially a company wants you to grant them the right to display your content on their site to avoid a copyright violation claim. In this instance, I am not sure that is the case, but I doubt Instagram is trying to steal and sell your photos. I do think it is worth watching for a week or so as people react and Instagram does some more explaining. For now I am going to post photos to flickr again ... at least until I can figure out what is going on. The fact that Kevin Systrom (Instagram co-founder) is posting a note trying to explain what is going on and what they really mean is encouraging; but it still gives me renewed pause as I wrap my head around what we exchange for a free service instead of money.
Advertising on Instagram ... From the start, Instagram was created to become a business. Advertising is one of many ways that Instagram can become a self-sustaining business, but not the only one. Our intention in updating the terms was to communicate that we’d like to experiment with innovative advertising that feels appropriate on Instagram. Instead it was interpreted by many that we were going to sell your photos to others without any compensation. This is not true and it is our mistake that this language is confusing. To be clear: it is not our intention to sell your photos. We are working on updated language in the terms to make sure this is clear.