More and more Stock Android apps is released in Google Play Store. We had the Android keyboard ripped that we could use for example, and after a while Google released it in Play Store, and now the Stock Android Camera app is ripped. My guess is that we will soon see that released in Play Store by Google soon too.
Google is changing android by doing this. They make Android more open than it already is. Look at the Google Edition phones in Play Store for example, now any high end device can run Stock Android and be sold through Play Store.
And manufacturers like Sony stops doing drastic changes to Android, and releases phones with very minimal changes from Stock Android. And that means that updates is released much faster than before.
Samsung is going their own way though, they want their own OS, that's why they are testing Tizen OS on some devices, and it's also the reason why they adding more and more features to TouchWiz.
All this together means that we get pure stock android, or almost stock on more and more devices.