I can't speak for anybody else, but I just wear one pair of synthetic socks with my trail runners. Typically, I use a pair of low cut, New Balance Coolmax socks. I find SmartWool socks to be a little too warm for my liking (until late Fall), but that's just my preference. So, generally, I prefer a thinner sock that breaths and drys quickly.
In warm weather, after a stream crossing, I simply let the body heat from my feet dry my socks. In cooler weather, I quickly (a) wring my socks out and (b) squeeze the water from my trail runners after a crossing and then put them right back on my feet. That's pretty much the extent of my moisture management.
If you're a runner, most likely you already have a pair of socks you can use.