The change log at 
ChangeLog.html
 describes the recents commits
to the CVS at 
http://cvs.gnome.org/viewcvs/libxml2/
 code base.There is the list of public releases:
2.6.12: Aug 22 2004:
   - build fixes: fix --with-minimum, elfgcchack.h fixes (Peter
    Breitenlohner), perl path lookup (William), diff on Solaris (Albert
    Chin), some 64bits cleanups.
   - Python: avoid a warning with 2.3 (William Brack), tab and space mixes
    (William), wrapper generator fixes (William), Cygwin support (Gerrit P.
    Haase), node wrapper fix (Marc-Antoine Parent), XML Schemas support
    (Torkel Lyng)
   - Schemas: a lot of bug fixes and improvements from Kasimier Buchcik
   - fixes: RVT fixes (William), XPath context resets bug (William), memory
    debug (Steve Hay), catalog white space handling (Peter Breitenlohner),
    xmlReader state after attribute reading (William), structured error
    handler (William), XInclude generated xml:base fixup (William), Windows
    memory reallocation problem (Steve Hay), Out of Memory conditions
    handling (William and Olivier Andrieu), htmlNewDoc() charset bug,
    htmlReadMemory init (William), a posteriori validation DTD base
    (William), notations serialization missing, xmlGetNodePath (Dodji),
    xmlCheckUTF8 (Diego Tartara), missing line numbers on entity
  (William)
   - improvements: DocBook catalog build scrip (William), xmlcatalog tool
    (Albert Chin), xmllint --c14n option, no_proxy environment (Mike Hommey),
    xmlParseInNodeContext() addition, extend xmllint --shell, allow XInclude
    to not generate start/end nodes, extend xmllint --version to include CVS
    tag (William)
   - documentation: web pages fixes, validity API docs fixes (William)
    schemas API fix (Eric Haszlakiewicz), xmllint man page (John Fleck)