Unfortunately the size of the GoT "viewing" fan base doesn't reflect in ticket sales for weekend events. There are a couple of regular GoT only events in mainland UK and in Belfast but the average attendee number is around 200 tops and an event planned in Italy this year managed to sell just a handful of tickets even with 1 main cast member announced.
If your referring to the con I think you are, she cancelled to work on The Killer Elite and subsequently got given grief by idiots on Twitter etc. to the point where she apparently has refused to book for an event over here
Gina would be awesome but haven't seen her name flagged at any events and read somewhere that she doesn't do signing events/cons. Do hope that's wrong though :)
Apologies if i've missed an obvious thread but is it correct that John Barrowman will only be there on the Sunday? Would be good to know for sure as I will unfortunately have to leave the con on the Sunday morning if I attend. Thx