It is the one-size-fits-all glove that the Open Mashup Alliance is hoping can clench down onto a formalized standard for mashup creation.
It goes by the name of Extensible Mashup Markup Language (EMML), an XML language that JackBe CTO John Crupi called a data-centric language that has the ability to invoke heterogenuos services, including REST, RSS, and WSDL services.
For a more thorough look at this supposed mashup savior, JackBe offers a short video that gives the 411 on all things EMML:
EMML Introduction
So my developer friends, please give it a once-over and share your thoughts on it! Tell us what you like, what you dislike. Do you think EMML has what it takes to be the mother of all mashups?!!!