Gazebo 2.x and 4.x have reached the end of their lives. We will continue to answer questions about these versions, but we will stop fixing bugs.
We are proud to announce the release of Gazebo 7. This version of Gazebo will have long term support (LTS), and marks a transition in our release process. A new version of Gazebo will occur yearly instead of every six months. Odd versions will have LTS, lasting five years. Even versions will have support for two years. This change will slow the rate of change in Gazebo, and give the developers a bit more time to polish features.
A large change in this release consists of a move to a consistent API, integration of Ignition Math, and a switch from boost to standard library features. You may notice numerous deprecation warnings as a result. While these changes may induce some burden on developers, it is important for Gazebo to advance toward a stable interface. Please pay attention to the deprecation warnings as the indicated functions will be removed in Gazebo 8.
Enjoy the new release, and thanks for all the contributions,
OSRF Development Team