> What's an edtf library supposed to do with URIs?
That is an important question! I was also feeling that we need to clarify 
our way to work with URIs, and therefore I suggested namespaces. We need 
to discuss those questions.

> I suggest that we take all the truly off-the-wall features and move them to level 3:
Four levels are quite a lot, but this could be a good way to gather 
elements within our specification. I suggest to create this fourth level 
(level 3) and then focus on the three first ones (level 0 to Level 2). 
When we are done and feel satisfied with these three ones, we could focus 
to the fourth level, having a stable and reliable ground (that is the 
three first levels).