So, what is my problem with Wikiversity? I am seriously worried that it may end-up to be just another platform for delivering learning materials - only. Period. I am afraid that Wikiversity community will not understand what are the factors that make a great academic institution. It is not tests, degrees and accreditations. It is the community.
Getting a dispersed community around whole courses or subject areas might be the impossibility for wikiversity. Wikipedia is fairly simple by comparison, in that it is largely focused around single entries... but wikiversity (at the moment) is trying to emulate a University, with faculties, subject areas and courses. The few times I have been in there, I have looked up the subject areas I am teaching with the intention of helping out, only to find a structure, related subject areas, terminology, and so much of it just not at all in an area I can help out with, or use. In other words, many 'entries' just may be too complex or context specific for broad communities to form around whole subject areas. On this, see David Wiley's 2001 paper, The Reusability Paradox.
At the moment, it looks as though Faculties from some universities are moving in and claiming the subject areas, structuring them the way they do at their own institutes, and hoping others will come in and help them with their work. That's great though, faculties going truly open courseware and all, but how can I join in? Do I want to? Or would I rather find another bit of turf in the wikiversity to set up my own version based on how I would structure the course specific to my own context...
So I think Wikiversity authors need to think of a way to simplify what they are doing, content and/or concept, linking it in with wikipedia a bit more perhaps, and considering what Teemu points out - how the communication part is so important.