I gotta admit, when I first saw friends posting pics with this new photo sharing app, my initial reaction was something like, "Oh please, not another social-photo network." For some reason, though, I gave it a shot, and now it's almost always open, or at least running in the background. It's even supplanted Bejeweled Blitz as my go to bathroo- er, time-killer app.
As a fairly new photo-sharing/social-networking app, it's got some very active members; all of whom seem to share the giddy buzz of being part of not just a new social network, but of being a part of a network that focuses on their favorite social networking features (ie photo-sharing, interactivity, ease of use), while keeping things simple. The interface is clean and intuitive, and it's easy to get sucked right in! Already, I've learned about some apps to help me further explore my iPhone photography.
Being pretty new, I haven't come across any trolls (yet), though I have stumbled across an argument. Another hallmark of a photo-sharing network with a bunch of new users: flowers, pets, sunrises/sunsets, and babies.
For the most part, though, it's people learning to take better photos with the camera they have most readily at hand. And who doesn't want to see better mobile phone photos? ;-)