I really liked this in the day (and i just played with the version you linked and can still remember all the key patterns - I'm typing this comment with it now).

But it just can't touch swiping for speed. Frankly, the keyboard I miss most is the T9 predictive text from my old school pre smart phone era.

Nothing has come close to the same expressiveness and speed while being usable completely blind, only by feel.

I do feel like mobile keyboards have stagnated in a bad spot, though.