The most recent release (0.8.1) doesn't work with the latest version of zeromq in homebrew (version 4.1.3). Since this was just added as a dependency of gazebo7, it is causing the gazebo homebrew builds to fail. It would help to make a new release as soon as possible just to fix the gazebo build.
Original report (archived issue) by Steve Peters (Bitbucket: Steven Peters, GitHub: scpeters).
The most recent release (0.8.1) doesn't work with the latest version of zeromq in homebrew (version 4.1.3). Since this was just added as a dependency of gazebo7, it is causing the gazebo homebrew builds to fail. It would help to make a new release as soon as possible just to fix the gazebo build.