Below is a youtube video on how alliance can get through the AB gates with enough time to cap two bases. The exploit uses the same concept as breaking through the EotS bubble before the BG begins. This is working on live servers as of 6/29/10.
Pardon the music... the video was not made by myself.
YouTube - WoW Arathi Basin glitch. How to get past the gates before the game has begun. Patch 3.3.3
Enjoy!
Searched for "arathi basin early gate" and yielded horde-only or outdated methods.