I'm working on a project that includes 6 different e-commerce sites. A few of them are on an outdated OScommerce platform, one is a Yahoo Shopping store, and two are custom built using Ruby on Rails. We would like to convert them all to one platform and make it so they are all driven by one central product database (our custom CRM and product management system built using Ruby/Ruby on Rails). The ideal solution would be a script that is well supported, well coded, has a strong API, and is flexible. We would need to set up a nightly syncing mechanism that will update product information across all stores. We also need it to talk to our system when orders come in. I have spent some time looking at SpreeCommerce, mainly because it's built on RoR like our system. But the coding language isn't necessarily critical. So long as the solution has a strong API we should be able to integrate it with our system. I'd like to see what others would recommend, given these requirements.