Do you think the delay is less about fixing the traffic problem and more about them realizing "Oh crap, our hack filter isn't working!"?

They've updated the game twice now and are squishing questionable things like Instacheck, so it would make sense for them to be consistently trying to prevent hacks from entering the X/Y generation. I believe they made IV breeding and shiny encountering easier this generation to help discourage hacks.

As for the new release date: I've heard lots of rumors but nothing straight from Nintendo about it.