Quote from: S4d1k (Source)

A little forewarning to those of you that play World of Warcraft on these systems;
Shortly before the release of Cataclysm, a patch will be released in which PowerPC processor based Macs will no longer be supported.
This update indicates the removal of PowerPC support from World of Warcraft.
Attempting to run the game after the update will bring up a message stating the hardware is no longer supported, and the game will not run.

Quote from: S4d1k (Source)

No problem. We are still supporting 10.4.11 and 10.5.8 until further notice. Some graphic features like the new water will require 10.6.4+.

Quote from: S4d1k (Source)

Even if you have PPC, you're still welcome to Blizzcon. I'll be happy to see you :)
We only decided to drop PPC very recently so that's why we couldn't confirm anything before.

If you're on a Mac and you're not sure what processor you have here's a helpful guide from Apple (Click Here)

Quote from: Mumper (Source)

The guild rewards you guys are seeing in game are not hooked up yet. Guild rewards have 3 requirements that must be be met before you can use them. First and foremost, they must be unlocked via a guild achievement. Let's just say, that for example, you need to complete the new guild achievement "We are Legendary" in order to unlock the Dark Phoenix. That achievement requires the guild to gain access to all 6 legendary weapons currently available in the game. (note that all guild achievements start on Cataclysm launch, so anything you have now will not matter, it must be done with your guild after launch)

So, let's say that your guild get's this achievement and thereby unlocks the Dark Phoenix on the guild vendor. At this point anyone in the guild can see the item on the vendor, but they will need a specific amount of guild faction to be able to purchase it. In this case, let's say exalted. Now, once you have the guild faction, you can purchase the item for its gold price. (prices will vary based on the reward)

I am using the Dark Phoenix and the We are Legendary guild achievement as examples here but you should get the idea. Don't worry, we wont be handing out all the goodies ...

Quote from: Blizzard (Source)

"We're proud to announce a brand new contest open exclusively to residents of Australia and New Zealand. We're looking for some tightly knit guilds who are ready to rumble their way into our World of Warcraft: Cataclysm beta test.
We want you to share screenshots of your guild's greatest triumphs and proudest achievements with us. Whether you and your mates just took down the Twilight Destroyer or you've crushed Kel'thuzad for the first time, we want to witness the milestones of your success.
Each guild master who submits a winning screenshot will win 10 invitations to the World of Warcraft Cataclysm beta test for their guild. The contest will be on for five weeks and each guild is limited to just one submission. We'll pick five winners each week for a total of 25 winning submissions from eligible participants, starting August 25, 2010. "

Quote from:Blizzard (Source)

The Contest shall commence August 25, 2010 at 12:00 AM PST (5:00 PM AEST, August 25, 2010) (the "Commencement Date"), and shall continue in duration until 11:59 PM PST September 29, 2010 (4:59 PM AEST, September 30, 2010) (the "Deadline"). All entries must be received by the Deadline to be eligible to win a prize.
(Character name and guild tag must be visible) which demonstrates why the World of Warcraft guild that the entrant is the guild master of should ...