Not sure which "two different releases" you're talking about. If you're discussing LR 1 public beta vs LR 2 public beta ... err, well, yes, they're very different. If you're discussing LR 2 public beta versus the final release form of LR 2, well they're reasonably close. The LR 2 public beta is not 100% feature complete. Those who follow the threads and announcements here can probably guess what's missing and what's coming.