I really liked the improvments of .191. Unfortunately, I can not keep it and only because of the camera. Although it is not a great one, I have 2 young kids that I send pictures everyday to my family back in the Bronx. When the camera issue gets fixed I am back on it. Currently, I am running .140 Hybrid from OOAK and I still have the flick scrolling from the switch from .191 with all of the missing stuff.
With all of these different versions of 5.0 OS, not one should still be using 4.7 OSs. The apps will catch up very soon and if the S2 is definately coming out at end of Sept/Oct, we can expect all of the social apps and other 3rd party apps to make amendments to fit the new product.