Minuum shows off its keyboard on Google Glass and beyond6
The video is pretty quick, but it does give a good look at what the team plans. Unfortunately, we're very hesitant about the initial idea for the app. Basically, the idea is to use the touchpad on the side of Glass as the input surface. Assuming you're forced to input text on your Glass rather than simply doing it on a smartphone, this doesn't seem like the best solution. Voice input is still the primary choice.
Even in the video that Minuum released shows an input method that would work better than touch typing on Glass: eye-tracking. Towards the end of the video, Minuum shows that it is already planning input that would follow your eyes, so you would input words just by looking at each character. That seems like a nice subtle alternative for text input on Glass.
source: Droid Life