I was able to install the driver by following the steps in matthew06854's post here.
Although the driver seemed to install correctly, I could not see the device under DDMS in Eclipse.
I was finally able to get Glass to show up under Eclipse DDMS on Windows 8.1.
With Glass connected, Eclipse running and DDMS visible (not sure if this really matters):
Open Windows Device manager
Expand Android Device
Right click on "Android Composite ADB Interface" and choose
"Uninstall"
Disconnect Glass and then reconnect
Android Composite ADB Interface should reappear in Device Manager
After these steps google-glass appeared in my DDMS.