Open means that the ARB decides what happens to the API. Unlike proprietary software like DX which MS controls entirely. It means that if all the ihv''s want some feature in opengl then it will probably end up as apart of the api. Where as everyone in the world may want some feature in DX but if MS says no, then everyone is screwed.
The fanatic is incorruptible: if he kills for an idea, he can just as well get himself killed for one; in either case, tyrant or martyr, he is a monster. --EM Cioran