W3C have moved the XHTML spec onto proposed recommendation status, which means it has about a month left for comments to be submitted, including the namespace debate currently raging on the XML-DEV mailing list. A new working draft has also been put fowrad for XHML Extended Forms, which aims to enhance form support in (X)HTML. New enhancements will include forms split across multiple pages, real data entry grids, secure submission and persistent forms tha the user can save for completion later. I think now is definately the time to start moving towards converting sites into XHTML - this one could be a good first candidate since it's already valid HTML 4.