Re: statically known namespaces

  I would have thought that XSLT 2.0 could benefit from having "xsl" and
  "xs" predefined, any thoughts?

XQuery specifies its own rules for namespace bindings so has full
control. XSLT defers to the XML namespace spec for definition of
namespace bindings so it would be harder to predeine these prefixes
for use in functions, and impossible for use in elements.
<xsl:for-each select="foo">
is not NS-wellformed if xsl is not explictly declared, and there is
nothing XSLT spec cam say to change that.

David