Hopefully not much. Putting in overpowered guild perks (Like WoW did) kills the whole guild system since people will only join for the perks.
Guilds should be groups of like minded people that get together to have fun, not groups of people that never talk and just abuse perks.
Nothing is really listed yet as a compendium, and people only know what they have seen themselves thus far. It seems items/guild halls/vanarch elections is it thus far but I'd expect there to be more. We'll see.
I'm also worried about guilds that are dramatically large getting vanarch positions through in-guild votes alone.
I've seen that video but it raises the question of what happens to the guilds that come later and want guild housing? How long does housing last? How do you handle supply and demand? Is it first come first serve?
I just have more questions than answers so I wait.