I would agree with what has been said before regarding pilot participation....its VERY well received!
Getting pilots and controllers together is always useful and dispels a lot of the myth and rumour about what goes on at each end of the mic!!! Had a pilot (from a certain Midlands based airport) plugged in with me once on my sector a while back and he was amazed at the issues we faced in trying to get him southbound on his merry way.
He left with a MUCH better knowledge of what the sector issues and constraints were and I believe he got a LOT out of it!!
This is a good step but it still amazes me why this is not embraced to a far greater degree by NATS and the airlines? I know it ultimately costs money from someone's pocket but the value in better pilot/controller understanding is huge!