I asked this in the Business Topics a while ago, before I started listing and the response I got was that generally it's easier to stay in your own currency, there are lots of GBP or Euro sellers aswell as USD and the buyers will see the price in their own currency anyway, they will accept that the number is round for you and not mind all that much about the conversion. As a seller from UK I've put my prices in GBP, makes it easier to regulate regular profits etc and it's not an issue for international buyers.
It's your choice though, these are just my thoughts based on what others have advised me :)