Paul Cotton, one of the three chairs of the HTML Working Group at the W3C, recently sent out mail reminding the HTML WG that there were a number of specifications written within other working groups that were issued as Last Call Working Drafts (LCWD). The specs  getting to this stage (and the working groups publishing them) are:

It's important to note that for these, "last call" does not mean that these specs are locked down and final. A last call working draft has a specific function within the W3C's process of moving toward a final spec, called a W3C Recommendation. Placing a spec into last call fulfills a number of steps that help bring the document closer to recommendation. Per the W3C's Process Document, the announcement and the purpose of last call are clearly defined :

Announcement: The Working Group MUST announce the Last Call to other W3C groups and to the public. A Last Call announcement MUST:

  1. specify the deadline for review comments;
  2. identify known dependencies and solicit review from all dependent Working Groups;
  3. solicit public review.

Purpose: A Working Group's Last Call announcement is a signal that:

  • the Working Group believes that it has satisfied its relevant technical requirements (e.g., of the charter or requirements document) in the Working Draft;
  • the Working Group believes that it has satisfied significant dependencies with other groups;
  • other groups SHOULD review the document to confirm that these dependencies have been satisfied.

In general, a Last Call announcement is also a signal that the Working Group is planning to advance the technical report to later maturity levels.

These definitions are important to remember as the HTML5 specification heads toward  a last call announcement, scheduled for May. Like the specs highlighted in Paul Cotton's mail, the HTML5 spec will not be finished but will be continuing on its orderly process toward consensus and recommendation. Certainly, there are questions about when user agents and your webpages should start implementing the new or changed features in HTML5. Those discussions are somewhat independent of when the HTML5 spec becomes a candidate recommendation, though. Of more interest to me, as the editor of the polyglot spec, is that the specifications enter a public review phase, where feedback that has been overlooked by the working group can be noted.