There's now quite a few Stack Exchange sites that are in public beta on Area 51. According to the Web Applications proposal, the "site's progress will be evaluated in 15 days" (as of this writing), so the "evaluation" is coming pretty soon.
What is meta?
- Any Stack Exchange user can ask a question
- The community provides support, votes on ideas, and reports bugs
- Your voice helps shape the way Stack Exchange operates
The usual process is that the site gets a "proper" theme and loses the sketchy theme of the beta. Also reputation privilege levels are reset to the same higher level as the trilogy sites. And that's it.
There are (currently) two exceptions to this.
Physics has graduated but still has the sketchy theme. This was because when the graduated theme was implemented it wasn't well received (despite being shown on the meta site) and hasn't been replaced.