I never had an instagram account and nerver used it until recently. I had to create and use one for a project I am working on. I was sadden by how generic most of the photo on the service are. Most of them are either black and white with slightly pushed contrast, or high contrast with a shift to either red or blue. Now those are common photo practice but instagram seems to have really standardized them (I guess the filters have a lot to do with that) in a way that make every photo look like the next one. And when there is a human subject, they tend to always use the same kind of "sensual" pose that you could find on the cover of a fashion magazine.

I am definitely sure that in this service use by millions of people there way more originality and diversity than that, but holy molly do Instagram tend to push those very generic profile down your throat and give very little visibility to original content. But I guess thats the issue with anything popular, it tend to aggregate around the most common denominator.