I noticed over the past week or two that a bunch of my Facebook friends have started using Instagram , a fairly recent newcomer on the social networking photo sharing scene. Apparently, Instagram is the New Big Thing in iPhone apps, although I seemed to miss the initial splash it made and am arriving late to the party. I played with it for a bit, and ... I wonder if I’m missing something here. Yes, you can share a photo on Twitter. About a billion apps can do that. Yes, you can share a photo on Facebook. Umm ... Facebook has its own photo sharing system that works a lot better than using Instagram to get a picture on Facebook. You can share pictures within your friends on the Instagram network. I'm not sure I want yet another social network to follow, thanks, particularly one that just shares photos. And Instagram also lets you "edit" and apply filters to your iPhone photos, ostensibly to improve the quality or look or something. Well, the photo on the left is an untouc...