I've created a new example of a PhoneGap app for my talk at the Atlanta Windows Apps meeting. The talk I did tonight didn't go all that well, but I got it working and the result is something you can download and see how to use a minimum of WinJS to build your Windows 8 apps.
The example PhoneGap app sourcecode can be found on GitHub:
Additionally, you can see the Win8 version by downloading the project I built during the talk:
If you were interested in the slides, you can get them here in PDF form: