This is not a new idea. I remember reading about something very similar to this back in '99 -- more than eleven years ago. Back then, it was touted as a faster alternative to
Graffiti on the
PalmPilot and intended to be entered with a stylus.
After some search, I think I have found it: "Quikwriting".
Read about the research project
here. The famous Ken Perlin (if you know a little about graphics programming, then you should know who he is) was behind this, apparently.
Of course, both writing systems are just implementations of the
Pie Menu concept, which is a few decades older.
Pie menus, with gestures to speed up navigation (called "Marking Menus") were significant in the user interface of the 3D graphics package
Alias (one of the direct predecessors of
Maya), so it is not strange that it was a graphics researcher that would come up with the idea to use it for something else.