I was thinking about writing a payment gateway abstraction layer to allow for developers to be able to change their payment gateway (Auth.net to Stripe, for example) without having to change their implementation code. Basically do for payments what PHP's PDO or Ruby's DBI does for databases.
A simple Google search to find if one existed discovered this patent by Microsoft: http://www.google.com/patents/US20080086417
What should I do now? The patent seems to be exactly what I thought of but as far as I far as I've looked, nothing was ever written. Can I still write one? Could I be sued for infringement? What if it was open source, does that change anything?