People apply for beta positions. Whenever Paradox announce their next new game, whatever it will be, keep checking the forum. At some point they will announce application for betatester, and there you go. Usually when the game is more developed they ask for a second-wave of betas (as they did with EU3).
As for writing an AAR, if I have the time, probably pretty soon.
As for writing an AAR, if I have the time, probably pretty soon.