As it was presented in OMG! Ubuntu! a voice recognition tool is being developed and will possible deploy in Ubuntu Touch and Ubuntu Desktop.
Although beyond the video shared in youtube I had no more information about that, rumors said that a testing ppa would be available for Ubuntu 13.04, although I didn't got anything else about this matter.
So if anyone knows about a testing PPA or any other way to test it share with us.
I'm one of the lead developers on this project. The voice recognition program that OMG! Ubuntu! showed is not being developed by Canonical. We currently do not have a PPA but you can find the project on GitHub.
We are also occasionally on IRC #speechRecognition
In order to install Linux Speech Recognition go to the project's GitHub page. Download the ZIP file and extract it.
Then install some dependencies:
Open the extracted folder (Palaver-master) in the terminal and execute the setup:
Now it is just to assign a hotkey to enable recording, in order to do that go to System Settings... > Keyboard > Shortcuts > Custom Shortcuts click the Plus Button to add a shortcut, name it Voice Recognition and set the command to:
Click apply, click over the shortcut and then assign a hotkey to activate Voice Recognition.