I've only seen 1 or 2 hammocks on camping trips. Everyone seems to bring tents. I've been doing overnighters with a few friends off a jungletraining forum, and there's usually just 1 every trip. I've been tarp camping myself, still waiting on my Warbonnet (seems likes forever). Once the WBBB comes in, I'll be doing 80% hammock.
I'm hoping to do a hammocks only trip in two weeks.