Blizzard has released a preview of the Druid Tier 13 armor set that will be available in World of Warcraft Patch 4.3. You can click on the above image to view a larger version. Here's their description of the Deep Earth Vestments:
"The design called for "phosphorescent mushrooms, reminiscent of Zangarmarsh," so our main concern was avoiding making a helm that looked like a giant toadstool sombrero. We’re always looking to incorporate interesting light sources within a raid set, and bioluminescent vegetable growth certainly provides that. Twisting, organic shapes are often key elements of a druid set, and this tier is no exception, with writhing plant roots providing a frame for the glowing clusters of fungi."
In addition to the Tier 13 reveal, Blizzard has posted a visual guide to druid Tiers 1-12 for Transmogrification purposes. You can view the druid's armor history after the jump, and check out Wowhead's guide to find all your old tier gear. Also, be sure to browse through all of the currently released Tier 13 previews.