We are planning to accept dollars, currently we are looking how to do it the cheapest way for our users without spending too much money on bank fees.
We managed to beat the EUR SEPA transafers. You can deposit or withdraw any amount in EUR SEPA and there are no fees involved, zero fees are good

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Bitstamp has for EUR SEPA withdraws 0.90 fee once your funds are converted to EUR and minimum amount for SEPA withdrawal is $10.00, so we pretty much beat Bitstamp here.
However beating Bitstamp in international USD transfers is a bigger challenge, currently we are exploring some possibilities, anyway accepting USD is a must have feature.