The EAP binaries have their own release cycle. The EAP 6.1 release cycle had a Alpha, a Beta which ultimately led to the 6.1 GA.
The 6.1 Alpha binary is made available for free (both for development and production use) to the entire community. This allows community users who have been using the community server JBoss AS (now renamed to WildFly) a chance to get the bug fixes and possibly other features which had been added while the productization work was in progress.
The 6.1 Beta binary is made available under the zero-dollar developer subscription scheme (the terms and conditions are herehttp://www.jboss.org/developer-program/termsandconditions). This zero dollar subscription allows users to use the binray in development environments but not in production, unless of course the user additionally is also a paid subscriber/customer of EAP.
The 6.1 GA binary is available for production use only for paid subscribers/customers. Zero-dollar subscribers can use it only for development purposes. In other words, the usage terms are the same as 6.1 Beta binary.