Blizzard is definitely not holding back information, as Eyonix on the US World of Warcraft forums posted Monday a preview to the new Mastery system for their 3rd expansion, Cataclysm. This is hot off the post he made about the stat system overhaul a few days ago. Instead of posting the entire thread here, I will just give an overview of the new system.

The Mastery systems primary goal is to eliminate the need to spec valuable talent points into boring choices in a specific tree. For example, if you are a Destruction Warlock, you always put points into Bane, which decreases your Shadow Bolt casting time and a few other spells by like a half a second. How boring is that! That is 5 talent points you HAD to use just to get to the more fun talents in the tree. Now with the Mastery system, the more talent points you spend in Destruction, for example, the more spell damage you will get and/or it may also reduce your casting time anyway. With this system, you now no longer need to spend talent points in specific boring choices because you will get them by just spending points period. Makes sense?

Here is an example of how Mastery would work for a Holy Priest:

Holy Priest
For each talent point spent in the Holy tree, the priest also gets:

• Healing – Improves your healing by X%.
• Meditation – Improves your mana regeneration from Spirit in combat. This would likely replace the existing Meditation talent from the Discipline tree, which many Holy priests consider to be a “must-have.” Regeneration will also probably be determined by whether you are in or out of combat, and not the “five-second rule.
• Radiance – Adds a heal-over-time effect to direct heals, such as Flash Heal. Mastery on gear would boost this bonus, and no other talent tree would grant it.

The other cool thing about Mastery is that it will be on high-end gear as well. It’s still a work in progress, so stay tuned as more information about this cool new system comes out!