The real question is: what do you plan to do if/when the site becomes populated so much so that it starts to look more and more like Reddit?
If you kept a permanent, absolute ban on image memes, I think you would avoid that. The problem is, and it will be interesting to watch this here, that every community eventually develops its culture, and in-jokes and "memes" (in some form, it need't be image memes) are a part of that. Whether they take over and destroy the place from the inside remains to be seen.
But without a downvote button here, am I expected to simply mute permanently anyone who takes part in something inane like a pun thread? If that becomes part of a certain sub-community's "culture," I have no interest in seeing it, but that means I'll have to never see any of those users' other non-pun contributions. I suppose that's their problem, not my own. EDIT: I'm in no way trying to criticize hubski or suggest that Reddit is inherently better - just trying to have a discussion is all!
Not sure, I'm still finding my feet. I can cope with the occasional pun, but image macros/memes are a 100% kill for me. So I guess I will end up muting anyone who does that. It will be a shame if they also contribute in an interesting way, but other good users will just have to fill that gap.
Steal all Hubski souls and run for the hills to feast on the yesteryears of humanity.