While I have yet to use the new UI to actually configure or modify an existing data feed I love the fact that I am now able to without the help of customer service. Thanks for making this thing happen and thanks for putting more power in the hands of users!
One request I have regarding this (FANTASTIC) data feed functionality - a connection confirmation dialog. For some reason, potentially user error, my FTP connection for the data feed was unsuccessful. I only found this out via email after hitting save. I'd love a "test connection" button in the interface to confirm I've set everything up properly.