They said they would keep us updated, and true to their word they now have a blog post out: "One Month In"
For starters, I was not aware that they had taken up residence at Pivotal Labs... which I view as a great move for all involved.
The post gives a view of what they are working on, lays out their plans for the rest of the summer and provides some screenshoots of a working Diaspora implementation.
They also include this video that shows messages propagating from one Diaspora node to six other ones. It's not necessarily super compelling video... but it gives a glimpse into working code. And, as they note, this is communication happening without any browser refreshes and without an XMPP server in the background:
All in all it's cool stuff and I'll continue to be interested to see what they come up with over the course of the summer!