Was literally just thinking the same thing! Event seems so empty compared to normal, especially considering its only 2 months away now!
While I'm sure this will addressed in due course, I have to be honest i'm starting to get a little concerned about this too.
As for my ideal guests...
GoT (Charles Dance, Dinklage, Harrington, Clarke, Coster-Waldau, Rory Mcan, Iain Glen, Jerome Flynn )
LoTR (ANYONE!!!)
Flash Gordon (In particular Brian Blessed, Max Von Sydow and Sam Jones)
Walking Dead (in particular Norman Reedus, Andrew Lincoln, Michael Rooker, David Morrisey)