Well, I like the looks, and it's interface.
It's a bit slow/heavy, most annoying was my notebook's fan going mad during the demo...
Aside from that, I believe it's possible, but it would require a lot of work. I can think of the following first steps right now:
* Checking out the configuration/optional components of the used built-in daemons and the possibility of using the daemons present.
* Creating some kind of automagical installation
* Building a server-manager interface for administration (panel)
The first would require extensive knowledge of those daemons, and would probably take up a lot of time...
I'd suggest a poll to see who are interested, both in using and in developing..
For now, I'm sticking with Open-Xchange, and I can't say I've got much time left for such a project.