lxml
====

* XPath namespaces support.

* XSLT support for parameters, Python extension functions, threading
  issues.

* XInclude support.

* Relax NG validation support

* better c18n support

* sharing the same libxml2 tree between DOM and etree. This will
  require a revision of the nodecache system, so that nodecaches can
  be more globally shared, and multiple types of nodes can be
  registered in it.

etree
=====

In general
----------

* test namespaces more in-depth

* will namespaces nodes of unknown namespaces be added (and never freed?)

Top level
---------

* parse() support for custom parsers.

* ProcessingInstruction

* XMLID

ElementInterface
-----------------

* optimize so that .find* functions run at reasonable speed.

* improve getiterator() implementation to use Python-level iterators

ElementTree
-----------

* _setroot(), even though this is not strictly a public method.

* parse() - this seems hard to implement sanely so this may be an
  incompatibility.

* improve write() support

QName
-----

Not yet implemented.

TreeBuilder
-----------

Not yet implemented.

XMLTreeBuilder
--------------

Not yet implemented.

XMLBuilder
----------

cElementTree interface. Need to figure out API.

XMLParser
---------

cElementTree interface. Need to figure out API.