There's a longer answer here than I have time to compose, but the summary is simply that we long ago abandoned the idea that A Big Rewrite was a good idea. Instead, we've been making numerous small tweaks to how Area51 operates, adjusting based on outcome, for roughly the past 4 years.

As such, the core philosophy (and bulk of the code) behind it is still more or less the same, but how proposals actually behave has changed dramatically.

We've also made significant changes to the lifecycle of sites after they're created, which you can find discussed on Meta Stack Exchange:

- https://meta.stackexchange.com/questions/260754/feedback-req...

- http://meta.stackexchange.com/questions/283663/its-been-a-ye...