The issue is that the templates of the plugin output everything in one area, and they don’t call genesis();
This means that you can’t use various functions that are genesis-specific such as navigation and other widget areas.
Whether or not you can start now is a good question! I suppose you will be a little limited for styling until you know exactly how the integration will work – are they writing a plugin (like Genesis Connect For Woocommerce) or are they intending to ship a child theme with it’s own set of templates that work within the Genesis system?
Are they going to leave everything within the geo wrapper, or split it up and hook the sidebar into the Genesis sidebar?
I am using another theme for the time being, just to get used to the plugin and putting all my style mods into a separate stylesheet. When the Genesis integration comes, i can decide whether to switch back to Genesis and my mods should be easy to transport.