2.0 is, as far as I know, very close to achieving "realistic" public Beta. We have two or three people testing it pretty hard for us, and are at the stage of fixing up all the "little things". Again as far as I know, all major features have been added, so we are at the "feature frozen" stage of tidying up prior to public Beta.
How long this process will take, I don't know.
Right now, I would advise against using 2.0 in any live context. We are still committing fixed code multiple times daily.
However, if you have a sandbox you can use, we'd love for you to load it up and start adding your feedback and bug reports. The more people who thrash it around, the quicker we can get the bugs squashed.
-- hugh