Previous beta weekends gave players access to the home cities and two explorable zones apiece for the Humans, Charr, and Norn, as well Lion's Arch and Gendarran Fields. In the upcoming beta, the last two playable races will also be open for exploration. Like the other races, Sylvari and Asura characters will see personal story content up to level 20 and access to their respective capital cities, the Grove and Rata Sum. In addition, a new Guild-Conquest PvP map will be available for playtesting.
If you've always wondered what sort of city snarky magitech geniuses would build or have been waiting for ever to play as a humanoid plant, your time is now.
[Edit to add: ArenaNet's blog post has been published, and Gamespot now has a video of Asura gameplay.]