Over the past 2 years I have drastically cut down on the amount of sites I am active on. At this point pretty much the only sites I actually post on are PD and smogon, and cosmo to some degree. Smogon sucks ass as a community, but its the best you can get for competitive pokemon. I am kinda holding out to get a few people behind me to leave and form a new site, but its hard since 90% of active members end up being swept into the system. For good new members you have like a 3 month period before they get a badge and become smogonites themselves.
I actively browse specific youtube groups and channels like the vlog brothers and amazing atheist, I can't imagine myself posting on youtube though. Its the same story for memebase and knowyourmeme.
So what sites are you active on, maybe we can expand each others blogroll and get more out there.