Is the new py api already done or well defined?

I wanna update my addons to 2.8 as soon as possible, but since it was a advice from the developers, I am waiting for a release. but its taking so long and I dont see many updates to python api to worry about.

I wanna know if I can update my addons already.

There’s any online documentation to keep track of the changes to the api?
I am concerned specially about the deprecation of the bgl module, I’ve seen something about a “Batch for shader” or something that is replacing the bgl, where do I find the details about it?

There’s still some rough edges and missing things, but you could start:
https://wiki.blender.org/wiki/Reference/Release_Notes/2.80/Python_API
https://docs.blender.org/api/blender2.8/