Blizzard is thinking of it all. With their two major upcoming new sequels - Starcraft II and Diablo III - as well as the new World of Warcraft expansion, they realize a lot of their fans are going to be playing a mixture of these titles at any given time. Therefore, it was announced today that, sometime before Cataclysm hits, cross-Blizzard chat will be integrated into Battle.Net. Why do I say "cross-Blizzard"? Because it will be available inside all three of their major franchise games and you can use it to talk cross-faction or cross-server in WoW, and even to friends playing other games.The details of this chat update are as follows:

"This [WoW cross-server chat] is exactly what we are working on implementing with Battle.net and real-life friends. You'll be able to add friends at the Battle.net account level and talk to them while in-game whether they're on the opposing faction, a different realm, or another Blizzard game entirely. This is coming prior to Cataclysm.

No one outside of your faction on your realm will be able to communicate with you unless you accept their friend request, or they accept yours. You will still have your normal World of Warcraft Friends list, but we'll be adding in the ability to have Battle.net players on your Friends list as well. The characters on your Friends list will allow the same communication functionality which exists today. It's only when you've confirmed someone as a Battle.net friend that you can take advantage of the additional communication features.

We'll get more into that soon, but it's safe to say in advance that you shouldn't accept a Battle.net friend request from anyone you don't know, similar to Facebook or other social networking media."

Of special note here is the fact that this will be available inside the games, with WoW specifically mentioned. So, you'll have your standard WoW friends list and then a second one with Battle.Net friends. So, theoretically, you can talk to a friend of yours playing Starcraft II, while you are raiding in WoW. Nifty, eh?