I'm an ex-Amiga user who has never seem any NG Amgas, FPGAs, etc.
What kind of things could I expect to see at this meeting?
Well - knowing many who will be there - you should easily have the ability to check out AROS, Morphos, and OS4 on several different pieces of hardware.
There will be a presentation on AROS (I am pretty sure) and I will do my best showing folks around on Morphos. There will be front projectors for the demos as well.