I feel like there are a lot less people "discussing" on all the audio forums, I am not sure if this is due to, people not liking forums, or not as many people looking into "high end" audio? I have also noticed less people at shows {not all of them} and less traffic in the hi fi shops... Also used gear seems to be going for a little less... Its not a dramatic dip but I can tell there are less people involved in the hobby lately... Other hobbies I have seem to be growing, Hunting and long range shooting have never been stronger, hot rods and classic cars are VERY strong right now, ect...
I used to log onto AH in themorning and look at the "recent threads" link and there would be at least a full page if not 2 and lately you are lucky if theres 5 or 6 in the list... Also we used to get at least 1 "what system should I buy for X amount" and now then are few and far between compared to my memory of recent past...