I can’t really retrieve the frequency on users connecting to the forum, since I only download the user profile data for the user part (and there, we only have a Last Active date, aside from the Date Registered).
Somethings can be done to get a rough idea though: i.e. compare the number of posts between two dates and if that number is above a certain threshold, classify the profile as active as per the definition you consider.

Perhaps talked about by forum members, but not officially. @theymos did state though the potential possibility of having a merit decay over time. What I think could be better perhaps, is to shift it (only the airdropped sMerits) on proportionally to current users, based on received and/or awarded sMerits, with the spirit of increasing global circulation and reducing risks of sMerits being stored in accounts that are not into the game.

I am not much of a social network fan, and basically stay away from them. With that in mind, my username was created with an old time meaning to me, but without the intent for it to be of much usage (I created the account on Bitcointalk without really intending to post much/at all). I don’t even use a personal avatar for the same reasons (I did during a certain campaign, but now that I can place whatever I wish, a blank avatar seems fitting for now).