The [release notes](http://wiki.blender.org/index.php/Dev:Ref/Release_Notes/2.72/UI/Pie_Menus) mention that it is possible to add pie menus. But I'm not sure how to do it.

How could I convert the mesh select mode menu's appearance:

![enter image description here][1]

to this?

![enter image description here][2]


  [1]: https://i.sstatic.net/PenNs.png
  [2]: https://i.sstatic.net/0yGpH.png