Our API directory now includes 239 messaging APIs. The newest is the Parseco API. The most popular, in terms of mashups, is the Twilio SMS API. We list 169 Twilio SMS mashups. Below you'll find some more stats from the directory, including the entire list of messaging APIs.
The new Service API provides a REST interface for publishing and requesting data, making Diffusion available to any programming language that can make an HTTP request – there’s no longer a need to install an SDK and developers can immediately start publishing from a command line.