I don't know that Poloniex has any plans to add USD, but you should absolutely keep an eye on @bittrex. They have made it very clear that they are in the works of adding USD along with a new and very much improved UI design to the site.
@bittrex-bill and @bittrex-richie have both made statements about it and they have been in the process of taking care of all legalities to get USD for months now.
Aren't these just pass-thru transfers to forex exchanges?
Not likely. I think they'll actually be a USD/BTC exchange.
@drc10101 & @stoner19
Either that or a ...
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