Is there any differences between nRf51822 and nRF51922?

Question

I noticed that nRF51922 has been public. It looks like the same with nRF51822 in hardware.

Ole Morten · Accepted Answer

Yes, the chips are exactly the same hardware, it's only the softdevice that's different. 
 The nRF51822 comes as a blank chip from the factory, so you have to program the softdevice yourself as part of your production, while the nRF51922 comes with the S310 softdevice preprogrammed, similar to the nRF51422.