The slack-api is a Haskell Library that works with and provides bindings to the Slack Real Time Messaging API. Authored by Matthew Pickering, users can program their own Slack bots using the functionality found in Web.Slack.
Once upon a time there was the great debate over JSON vs XML. The past few years have seen JSONs popularity rise despite XML (and other formats) being well-established. Our own statistics on ProgrammableWeb show a significant increase in the number of JSON APIs over 2009/2010. During 2009 there were only 191 JSON APIs registered. So far in 2010 there are already 223.
Campaign Monitor, the email marketing software aimed at designers, recently announced a massive API update that is sure to please developers. The changes are less of an update and more of a complete redesign from the ground up. The folks down in Sydney have gone RESTful, the new version no longer supporting SOAP. The API also added realtime tracking and integrated powerful segmentation tools.