Now renamed to Bisq : https://bisq.io
Monero can be traded on the Bitsquare Decentralized Bitcoin[...]
I'm posting this for those who may not be aware. Bitsquare is a fully decentralized bitcoin exchange where you can trade fiat currency and alt coins including Monero. Privacy is a priority on Bitsquare and trading is done via Tor hidden services. Trading is actually p2p, you don't send your coins to an exchange. Traders trade directly with one another using 2-of-3 multisignature transactions. Bitsquare utilizes arbitrators for dispute resolution
https://bitsquare.io