Nope. There won't be any new features (new lockscreen will be avaliable with the final release once it's out globally ) and some bug fixes with OEM firmware update that should bring new drivers for the device.
There should be some stability in final release because dev preview is struggling when changing between background apps.
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Everyone will get an update when the official release is out, the official release will include Dynamic Lockscreens, Bluetooth 4.0 support and alot bugfixes and other stuff i can't really remember.