Originally Posted by IMH

Some payment processors keep everything (and get merchants to sign up by persuading them that it's great for their customers and "there is no cost to you"), others appear to pass most of the additional FX margin on to the merchant (see the section "how we make you money" near the bottom of this page for an example) -- although we can assume that this is not an act of generosity: the payment processor will benefit from the higher amounts being charged and may well be charging more for terminals/software etc. in the first place.

Originally Posted by continuumcommerce.com

Your customers will have the ability to pay in their own currency which is a great customer service benefit, particularly if they have been surprised by payment amounts on their billing statement in the past.