The document has issues but I'd guess those'll be fixed as things evolve. (This being
an early review.)

The main issue I see is scope - I'm not clear what the document's scope is or should be. 
The text is very general, but the examples discussed seem rather limited, e.g. with no
mention of the handling of DNS names in e.g. email, ssh, anti-spam blocklists or things
like infratructure tools like cPanel. Put another way, if the scope is intended to be
as broad as the text, then there're a lot more quirks to using DNS names that are in the
current text. But perhaps some much more limited scope might be easier to finish and 
still useful. I'd encourage the authors/WG to consider that. I don't myself have any
strong opinion, but I'd say that not fixing this issue might lead to much pain later;-)

As a near-nit at this stage, I'd also note that various UTAH WG documents discuss
handling names in TLS which is a subset of this I guess.