Just wanted to give a big thanks to Block.io and spread the word to other web developers interested in coding Bitcoin payment gateways. I was able to code a Bitcoin payment plugin (for Joomla CMS) for a subscription site in less than a day.
This isn't meant as a plug but here's the sign up page for proof.
My code uses the API to generate an address. Google charts api generates a QR code. It then uses the Block.io API to check the address for payment every 3 seconds. I could have used the notifications API for this but it seemed easier to use the basic API to check the address balance every few seconds via javascript from the browser.
As soon as the payment has been made it generates a confirmation and redirects to a confirmation page, simultaneously enabling the user's account.
The Block.io account with API access was completely free. I was actually a little shocked at how easy it was. Seriously, took about 4 hours to code and test.
Block.io Website: https://block.io/
API documentation: https://block.io/docs/basic
Thanks guys.