According to this interview
http://venturebeat.com/2015/01/08/wh...ire-interview/
Out of those if we split pro rata of the current steam graph score
Tw:R2 22 k
Tw:S2 5k
E:TW. 5 k
N:TW. 2.5k
M2:TW. 2.5k
It means approx
500 k active player for TW : R2
Rest of interview is interesting too