The toolkit is available from the Robotics Toolbox for MATLAB svn repository (you will need svn to check out the code from here).
It can also be downloaded as a zip file . The toolkit source can be browsed on the Google code repository . A video of a 2 DOF robotic arm using the software can be seen in the video below.
Installation Notes
The toolkit should work as is. The USB libraries required to connect to the EV3 with Windows and Mac are included (no additional USB drivers are required). Mac users may have to install Xcode if the USB connection loading fails. You will need to modify your MATLAB Java class path if you wish to use a WiFi connection as mentioned .
Note that the toolkit code will work on the default firmware of the Lego Mindstorms EV3!