This was recently discussed in another thread and brought up by Gijs, many of the logos and banners we are currently using, are based on old versions of FlightGear, but FlightGear has improved a lot since then.
So it would be great to have some updated logos and banners, that we can add to our wiki for people to use when advertising FG: http://wiki.flightgear.org/Logos
Given the amazing talent available in our community, it should be easy enough to come up with a bunch of new logos and banners, right?
For example, quite a while ago, Michat created a fantastic custom splash screen for flug's bombable addon:
So, maybe we can come up with a similarly impressive banners and logos that advertise the latest FlightGear features?