yes the only area effect that I've seen work is "remove your house that was place before the arenas were by friday or they will be removed." Just one more reason subscriptions are falling since my occolo house had to be removed -1 householder account. useless unwanted content for the win.
i have an idea lets make an arena in luna and see those houses forced to be dropped. but hey I've been around long enough to remember that you were not ever going to be able to place large towers,keeps or castles in malas , just an 18x18, and thats changed , who knows after 5-6 years of unuse maybe they'll give me the arena as a replacement for my house.