Implementing a Google Checkout Level 2 integration is a huge pain. I hope to blog or make a PeepCode Screencast about it, but it involves:
* SSL on your server
* A state machine to keep track of the half-dozen states that an order passes through before being charged
* An external messaging server or queue so you can send notifications to Google at the right points in time (I use acts_as_state_machine and a cron job that calls a Rake task)
The benefit is that Google is inexpensive. However, many consumers (even developers) prefer to pay with PayPal. PeepCode purchases are about 65% PayPal and 35% Google, but I pay about 4% in fees to PayPal and 2% to Google.
So examine your options and the customers you are selling to. It's nice to offer multiple options for payment.
Last edited by topfunky (2008-07-15 13:54:30)