Coming along next reboot or so, the anti-gang code will have a similar effect upon area skills/spells/powers/communes. Your allies can provide cover and generally get in the way of you being able to clock someone with a tsunami or what have you.

Are area effects now useless for ganging? No, but they're in the same boat as directed effects.

Are area effects now useless for group vs. group battles? This would be my biggest question if I read this announcement, and again the answer is no. It will work something like this: Let's say you are a conjurer and your four groupmates are fighting an enemy group of five and you're all focusing on the same one guy out of the enemy group. If you cast flash, four of your enemies are affected as normal. The fifth dude you're all wailing on, however, has a good chance to be safe from the spell because he has the cover of five characters wailing on him. Area effects are thus slightly diminished for group vs. group action, but they're still the best game in town for these situations by a wide margin.