When Instagram 2.0 came out I was pretty pissed off with it. There's a lot of retro Photo filter apps out there but Instagram 1.x had a good range of looks, a lovely atmosphere to many of the filters, and a great sharing mechanism that really kept the number of taps required to a minimum.
2.0 made a number of significant and subtle changes to the filters. They added Live Previews before you take a shot, but they removed much of the character of the filters including all the textures that gave the a filmic feel. They removed some filters altogether, notably a particularly lovely black and white called Gotham leaving just a watery contrast-free effort that rarely has much to offer, especially compared to the b&w options in something like Hipstamatic. And they added a few new filters, which all looked kind of similar to me.
I ranted about it, to no avail obviously. In time I was back using the app daily and grew to like some of the new filters (I find myself using Amaro almost exclusively) but I almost never posted another B&W with it again. I concluded that the muting of most of the filters had to do with the tech they put in place to do live previews.
Whatever the reason was, it seems that with the latest update, iPhone 5 users can't do Live Previews any more. I'm happily sticking with my 4S and I have the feature still available, but I never use it so I don't really care; I take the photo first and pick the filter later or I'd miss the moment.
Some believe the live previews being on their way out could be a symptom of Instagram dragging the iOS app down to the same capability of the Android version, so there is 'parity'. That is, giving iOS users the same experience Android users get because that's easier for Instagram to maintain, and/or presents a more unified experience (which to me, if they actually used that latter claim, would reek of a bullshit excuse).
On the other hand, it occurs to me that maybe they figured that live previews are kind of pointless because you can pick any filter you like after shooting your snap and not save it until you're happy. To me it seems plausible that they could just be streamlining out a feature that doesn't offer all that much; keeping it simple Jobs-style, knowing when to say no?
This change certainly won't make any difference to the way I use Instagram when it drips down to us 4S users, but nonetheless I would love to know the real reason why they're doing it. Objectively, I can't decide. Cynically, I know exactly which one I'd bet on.