Unfortunately, Rapid7 recently informed me that they would no longer be including msfgui from the official distribution of Metasploit (along with Armitage). This means that the only bundled interface will be the new web interface and the console version, which are backed by Rapid7. But don't worry, because even though it is now a separate program, msfgui is still supported and still provides (in my humble opinion) the best way of harnessing all the power of Metasploit. After all, it is 100% open-source as always and will never require registration or serve advertisements.
The new home for the msfgui source code will be https://github.com/scriptjunkie/msfgui - if you can use git, checking out that repository will be the best way of keeping an up-to-date copy.
Msfgui is now available in an installer for Windows. It will still integrate directly with Metasploit, and if you do have Metasploit enabled as a service, should connect without any hassle on any platform. I do not have an updater for Windows. The windows installer can be downloaded from here: https://github.com/scriptjunkie/msfgui/blob/master/msfgui-installer.exe?raw=true
The past three years have seen msfgui provide a solid interface, expand in capabilities, and be used world-wide, even in languages I can't even identify. With any luck, the next few years will bring even more!