As Eldorian highlighted in our Mists of Pandaria press event coverage, the Druids get a very nice set of new glyphs which grant new forms.
First, I have to specify there are only two types of Glyphs now: Major and Minor. The prime glyphs were removed.
The video below will show the Orca, Stag, Treant, and Astral form. The Treant glyph adds an icon to the Shapeshift forms UI letting you shift into treant any time you wish. The Astral form seems to be a placeholder. Currently, in early beta it only transforms the druid into a ghost using a more light-blueish Shadowpriest glow. When the druid mounts a flying mount the mount also has the Astral form. The Stag and the Orca look fun.
The chameleon glyph basically makes your druid shapeshift into a different-colored cat form every time you shift. The bear version is not yet implemented in beta. It might be added at a later beta patch.