The hair and earring customizations are live in the MoP beta right now. Unfortunately, the button for the hair streaks has not been implemented yet, so currently you're given a random color when you create a character.
To see all of the new highlight and earring options, head over to Wowhead News.
It's open warfare between Alliance and Horde in Mists of Pandaria, World of Warcraft's next expansion. Jump into five new levels with new talents and class mechanics, try the new monk class, and create a pandaren character to ally with either Horde or Alliance. Look for expansion basics in our Mists FAQ, or dig into our spring press event coverage for more details!