I don't know about those beacons, but I'll tell you exactly where Ardupilot is heading:
Apparently transponder data from the existing commercial traffic system is already available freely and easily on the internet. So the Ground Control software guys are patching it in. You'll be able to sit there with a laptop and a wireless connection, and get airline traffic info right on your screen. We actually have this running in a beta version right now. The next step, I believe is to try and have us put out location data. The idea is that, actually having a transponder on a small aircraft is kind of unworkable. But you could have the the ground control software do it. The laptop knows where the UAV is, and so it can transmit the data on behalf of the UAV. So you'd have a transponder attached to the computer, or maybe it's fed through the internet, not clear to me at this point.
Probably be another year before this is available, but it's on the way.
I would like to add exclusion zones around airports, but it's a really difficult thing. Some developers think that it shouldn't be the responsibility of the software to make people fly safely. And many users think that we shouldn't "give in to the man", they see personal-UAVs as another battleground to fight the power. I disgree with both stances. Part of the problem is that the exclusion zones are really quite large. In some populated places it can actually be difficult to get outside of one. People have been flying RC airplanes within 5 miles of airports for a long time. In fact, the AMA and MAAC regulations even allow it. The official rule is what, not higher than 400 feet if within range of an airport? I would think we could do something like... maybe not a total exclusion zone, but enforce a 400 foot limit between 3-5 miles from an airport, and then 100 feet from 1-3 miles. And then total exclusion, within 1 mile of the airport center, which would actually be good for security purposes.