16 Legacy points for all beta testers

Many testers are busy collecting Legacy points right now. So that everyone can test the system without first leveling several classes or farming dungeons, Blizzard plans to give all beta testers 16 Legacy points.

When: "in one of the coming beta weeks". There is no exact date yet.
How long: until the end of the beta.
What you need to do: nothing, the points are added automatically.

16 points is exactly the maximum a character can spend.