Yeah. It does suck and unfortunately there's not much we can do to get projection. That said, there will be flipcharts if you want to draw anything out. My other suggestion (which you have probably already considered) would be to have an etherpad with links to launchpad or slides that people can easily get at so that you can look at the same thing together.
Just a thought, but maybe (time permitting) you could prepare a small lab sort of thing, like how to check out the code, run unit tests for Keystone and how to assign themselves some low hanging fruit. Focus more on a hands on type of thing than a presentation?
-Kendall (diablo_rojo)