We've released a fix for the black-screen-on-boot issue. You are experiencing this bug if you boot your computer and see either:
A. A black screen with a flashing cursor in the upper right.
B. A black screen with the mouse cursor in the center.
The fix is being distributed through the System76 PPA, which should be installed if you have the latest driver (13.04.8 as of the time of writing). The update will be distributed through your Software Updater application with your regular software updates. If you're experiencing the black-screen issue, then after booting up and getting to the black screen, you can type your password, followed by enter, to log in and update.
If you don't have the latest driver, you can add the PPA for it by running these commands:
You can then install any available updates to install the fix.
sudo add-apt-repository ppa:system76-dev/stable
sudo apt-get update
sudo apt-get install system76-driver