why is Poloniex's trading volume consistently so much higher than a number of other established exchanges?
The offer a somewhat reliable service (no downtimes and no endless waiting for the funds to get in), and the layout it's good.. that's about it. Everything else is just pretty much luck. An exchange is limited to giving you an experience that is as reliable as possible for as long possible, Poloniex seem to be doing this, until it goes Cryptsy, I hope it doesn't.
I thought that when they forced people giving real names to withdraw crypto the exchange would crash because everyone was leaving, but apparently it survived (no one uses their real names anyway).