I didn't listen to the whole thing, so I;m not sure entirely where they took it, but the idea was that they were sort of anti-entropy. The backstory was kind of things like portals and teleporting (in their idea) weakened the fabric and stability of reality so they would show up to prevent you from doing that.
The powers they were talking about were kind of along those lines, like preventing you from teleporting, or telporting you when you tried to teleport it and stuff.
They were at GenCon, I suppose and they gave a list of monsters. The one with the most votes would get a 4E upgrade. Modrons won, hands down (it sounded like froghemoth came in second).
They were just throwing around ideas.
Again, it was an exercise in creativity.
They had ideas like
* The assumption was to make them living constructs and the immortal type. They were using DiTerlizzi's modrons for reference, but they did have images of the original modrons (which got a repulsed reaction from the audience).
* they opposed entropy, and especially the slaad.
* They opposed planar travel and wanted to keep each plane pure. PCs would interact with them when they start using teleportation and planar travel powers. The modrons believed that it harmed the planes when this kind of travel was done. Maybe they are correct? This was brought up to give them some wiggle room and not just be enemies to kill.
* They made a comment that they would want to think of a story for the modron so there could be a potential campaign built around them, or even modron PCs (Rogue modrons and Nordom from PS: Torment was mentioned)
* They did not want to make just brutes for PCs to fight and kill.
* They were thinking of a gimmic for the creatures. A power of some modron might be that they could drain hp of lower caste modrons to stay alive.
* Scribble mentioned other possible powers.
Again, it was a creative session. I guess they WILL be used in 4E eventually because of this.
I never got to finish it, and I can't hear it at work so that's all the info I can provide.