"When I block them, I just don't want to hear from them any more."
This is what we've heard over and over again from players in the Forums, in help cases, and in one-on-one conversations whenever blocking another player was discussed. Because it's not the case that every person who offends or annoys you is actually someone you'd want to report for abuse. Sometimes you just want the ability to tune them out.
So, yesterday we added something to the way blocking works. Now when you 'Block' someone, you won't see anything they type into any chat, whether it be Local, Global, Group or Party chats (unless you happen to unblock them later).
It's taken some time to get here because we wanted to make sure it wouldn't introduce complications that a less involved block could avoid. For one, we talked about whether the potential for causing confusion by muting certain players in all your chats outweighed the benefits of not being exposed to them. In the end, we thought it did. This is the first of a few changes we'll make to blocking, and I'll make sure to give you updates on the rest of them here when they're all set to go.
Update! (11/14/2011): Players you've blocked will no longer see growls about your arrivals, departures, and achievements in Local Chat, so you have a little more privacy as you move around the world.