the most popular by far is paypal, but following that, the main ones are: nochex google checkout alertpay
I can say, Paypal is still the best online payment gateway because it supports many options and features... and user-friendly too...
GUYS I JUST WANT TO WARN YOU, THIS IPAYDNA IS FRAUD, three of my best associates were not paid last year at the end they held over $70000.00 in payments for one of them with excuses, reported false processing, they sometimes offer to take care of shipping products when it is about shippable goods, well don't do that you will lose your customers, they send fake stuff, after a while and held all your money for the chargebacks and refunds for fake products, and for sportbooks they wait until you have enough on the account to then keep all the funds. They always delay payments, so fraud, keep an eye on these guys they have been banned in many other forums.
Yes they are scam, look here for an proof, this person was owed $37000 by Ipaydna and just got paid for around $2000. This guys at ipaydna.biz are nothing but amazing thieves
PayPal. And it is better than a "gateway". These Gateway shysters are not up front about all of their "secret" charges. Please don't take my word for it, go get one for yourself. When they charge you 15 dollars for a blank piece of snail mail paper (an invoice) or they tack on an extra.05% "handling fee" that you didn't exactly catch in the fine print, then you will understand why PayPal is preferred. You can get eCommerce gateways that are legit, but you best have a decent revenue stream to substantiate all of the extra charges, etc. If you are running a small site selling under 5 grand a month in inventory, you are better off using PayPal. Even PayPal offers high-end merchant services. So it is all there if you want it. And you can actually talk to a HUMAN BEING if you have issues. Most others you will talk to the "machine" and that's about it.
We are B2B, selling services to eCommerce but even for that PayPal does a great job. Not sure when it will be a point for us to consider a full blown gateway...
Yes, I think so also that PayPal gives a lot of nice features and also the most important thing - security.
From my point of view and experience the best payment gateway is PayPal. Easy to write script, Supports credit card and online banking system too. Regards -Gudiya