In my country any of them is supported, only Moneybookers (but they froze my account with no reason...) so I became used HooPay because I can make withdrawals to Cayman Island. It has 19 currencies supported, I can send faxes and SMSs arround the world, I have instant html buttons, api with digital signature, only 1% of received value is charged, deposit with credit card... Cheers
Being that our company is in the US, we use a merchant account connected to our own custom applications via Authorize.net. This is the primary means of payment acceptance for us, followed by PayPal, then wire transfers.
I've actually been floating towards the merchant accounts right now as trusting online merchants such as PP can be quite a hassle when you're making too much money with them =]