There's a fascinating thread on the official forums about the way that Blizzard is changing the global cooldown. The long and short of it is that on live, we can spam our next ability to try and increase the number of actions we can get in per minute; however, if we change our minds, we have until the next ability is accepted by the server to decide to change the keys we're spamming. In Cataclysm, there'll be a completely different system. First, let's look at the blue posts, and then we'll talk about the explanation.
On Monday, we got this:
Today, Kalgan added:
Let's talk about this. In Cataclysm, the way things are now in beta, if you hit an ability while the global cooldown is still counting down, the server will accept the command and hold it for you until the cooldown (on the server side) is finished. What this means is that if you have to cram as many abilities into a minute as you can, you will be able to chain them together one after another, no matter how bad your latency is. This is awesome, because right now, it doesn't always work out that way. You currently have to press a key as fast as you can and hope that the second the server starts accepting commands for your next cooldown, one of them landed. If your latency changes, or if you don't spam as fast as someone else, they could land more abilities in the same period of time.
The downside with this new ability chaining system is that if you send a command that's received half a second before the server is ready to execute your next ability, you can't change it. There are many reasons you'd want to do this, including procs, buffs, debuffs, boss mechanics or even better abilities coming off cooldown. Ghostcrawler's post indicates that Blizzard is planning on letting us change our command after it's been queued, though.
In addition, Blizzard will be implementing a new feature that lets you configure how early the server should start listening for the next command. It will eventually default to your average latency, and the closer it is to your latency, the better. Setting it high would be a perfectly fine option if we are indeed able to change our minds at the last minute; otherwise, it's better to stick to having it set at your average latency.
World of Warcraft: Cataclysm will destroy Azeroth as we know it; nothing will be the same! In WoW Insider's Guide to Cataclysm, you can find out everything you need to know about WoW's third expansion (available Dec. 7, 2010), from brand new races to revamped quests and zones. Visit our Cataclysm news category for the most recent posts having to do with the Cataclysm expansion.