A good Ares vs. everyone, a good Deathstroke vs. everyone, and Killer Frost vs. the cast. A lot of rumors will be put to rest this weekend, and some things will be substantiated that weren't before.
Also I'd like to see how people handle Jeremiah's doomsday, and if Dizzy's Aquaman matches up differently than Tom's.
Slips is there so you're guaranteed your good Ares. 16 Bit is there so you're guaranteed a good Killer Frost. He'll likely play your buddy PL as well. M2Dave is there so you're guaranteed your good Deaths...Oh wait. There's always MIT then.
I too, am very interested in seeing Dizzy's Aquaman, which based on the way he and Tom play in general, should be different from Brady's.
To be honest, I just want to see GGA dominate so 16 Bit can pop off on REO for claiming nobody is on he and Tom's level. 16 Bit is awesome at pop offs in general, but more so at people who are not present in the room. Random pop offs are my favorite.