PayPal doesn't like seamless integration with external websites. They make their money by sheer volume of subscribers and by putting their logo everywhere they can, so they like people coming directly to their site. Because of this, they have intentionally made it very difficult to integrate their payment options into websites if the person who is paying doesn't already have an active account. I used to send PayPal variables to populate the customer's info that I already had from my website so they could just verify it and click on through. Not anymore.
This, combined with some issues I've heard about PayPal security and their pointless restrictions on what they choose to sell (doesn't affect products I've designed websites to sell - it's the principal of the thing) have prompted me to search elsewhere. I've found some alternatives, but none that I'm willing to recommend yet.
-Ben
