Everything is moving along on this. At this point, we’re getting reasonably close to rolling out what I’m calling “phase one” of the MDC upgrade. This will be MediaWiki 1.9.3 with everything else roughly the same as it was before, except we have some new MediaWiki extensions installed that will let us roll out some of the other new features fairly quickly.
The second phase will be to implement some cool new templates. These have already been implemented in the staging wiki, so it’s mostly a matter of copying them over to the real one and then updating various articles to make use of them.
The third phase will be to do the more substantial overhaul, including reskinning the site to match the rest of Mozilla’s look and feel, fixing assorted bugs, and implementing our new breadcrumb system.
That third phase might come in stages as well.
At any rate, if you’d like to see the progress in more real-time, you can keep an eye on my to-do list page. That keeps a list of all the work we plan to do to MDC, and shows what’s already been done on the staging server.