Some people say 2016 other say two months.
I'd personally be so glad to see the new version out. The betas have looked great and some of the new features are absolutely awesome. Servers such as Argonath RPG will be able to push the boundaries of player-to-player interaction, while more casual deathmatch servers too will benefit, particularly from the multifarious environments which they can design.
I am sure no efforts to create this will go to vain.
The reception will be a good one - the community that I am in, which has been home to around 3500 users just on the forums, will be supporting 0.4 from the word go. Similarly, other servers and wider MP communities I'm sure will respond positively to a release that has been so long in the waiting.
We all look forward to it. : D