Reforging, which we mentioned two weeks ago here, is finally active in the beta. It is a rather simple process—Alliance side you will need to visit Ithurian Whitespire in Stormwind near the Stockades, ask a guard for the nearest Thaumaturge. The Horde equivalent is Enchanter Farendin in Orgrimmar's Cleft of Shadows. When you speak to the NPC, it asks you to drag and drop the item you want reforged. After dropping the item in the slot it asks which stat you would like to reduce and what you would like to increase.
An example (which is in the screenshots) is taking 32 Haste Rating from Lasherweave Cover, and adding 32 Mastery Rating to it. After clicking Reforge, it will make the changes—and bringing any reforged item back and clicking restore will turn the item back to its original form. As this example is a Tier piece which cannot be vendored it only costs 1 gold while any other pieces will cost their vendor price.

Reforging Now Available in Cataclysm Beta

Reforging Now Available in Cataclysm Beta

Reforging Now Available in Cataclysm Beta

Reforging Now Available in Cataclysm Beta