The W3C has released Last Call Working Drafts of two key standards for hypertext linking in XML: XLink and XBase.

XLink appears to be largely unchanged from its previous draft, although it has a new namespace (http://www.w3.org/1999/xlink) and four new sections on element type relationships, attribute value defaulting, integrating XLink usage with other markup, and using XLink with other markup.

A recent message on www-xml-linking-comments acknowledges that two of the original requirements for XLink have not been met, particularly in regard to legacy compatibility and DTD-based remapping.

XBase, which is only in its third draft, is a companion to XLink that provides functionality like the HTML BASE element, defining a foundation URI on which relative URI's then build. There are some questions about the need for XBase, but it seems to be on a fast track for development.

Last Call for both drafts ends 20 March 2000.