Tom,
Yes, this is on our internal Wish-List. The goal is to have a All-Inclusive flight planning solution. My vision, thought it might be a little different than Walter's, would allow you to plan a flight online and "push or publish" to your user account. Then you could pull in that Flight Plan from your account via the wi-fi on the 720 or export as a GPX file for use on the 520 or 700. The end result is to get a complete flight planning solution online to integrate with the iFly.
Currently, you can plan a flight on some alternative sites like the AOPA Flight Planner, Flightsoft, or EnFlight and they have an option to export or save your flight as a GPX file. You can then put that GPX file on a USB thumb drive and load it into your iFly from the USB drive via the Flight Plan page. This works very well at this time. I hope this helps.