Notes on XML and Media Types

Changes from RFC 3023 to 3023-bis
  http://www.w3.org/2006/02/son-of-3023/latest.html#anchor45
  text/xml and text/xml-external-parsed-entity deprecated
  XPointer ([XPointerFramework] and [XPointerElement] added (fragment identifiers)
  XPointer Registry ([XPtrReg]) mentioned
  [XBase] added 
  charset language now conforms to TAGMIME
  many references updated

Outstanding issues:
text/xml or text/*+xml with missing charset parameter
  applications all rely on the xml encoding declaration
  MIME says to assume US-ASCII (good choice for text email, but...)
  RFC 3023 says to assume US-ASCII - universally ignored requirement
  RFC 3023-bis proposes to deprecate text/xml
  existing non-ASCII content (like RSS feeds, xslt) served as text/xml not going away
  deprecation rejected by implementors: not a solution. FIX text/xml instead.

text/* vs application/*
  email and HTTP differ in emphasis and goals here
  is the original distinction still relevant/important
  http://www.mail-archive.com/whatwg@lists.whatwg.org/msg20855.html

HTTPbis ISSUE 20 may help here
http://trac.tools.ietf.org/wg/httpbis/trac/ticket/20

Closed issues:
Inconsistency with W3C TAG finding Internet Media Type registration, 
  consistency of use [TAGMIME]  http://www.w3.org/2001/tag/2004/0430-mime
  Don't add a charset if its unknown, or differs from the encoding declaration
  Unambiguous when charset omitted
Generic processing of fragment IDs in RFC 3023bis
  extensive TAG discussion
  XML vs RDF/XML handling
3023bis and XPointer
  element() scheme required, or not
XML 5th edition vs. 4th edition