In this post last April (that I've only just found), Dave Shea explains why he's moving back to HTML 4.01 strict from XHTML: mezzoblue - Switched.
This is newsworthy, as the W3C have just announced the effective merger of the XHTML2 and HTML5 efforts, as the former's charter expires at the end of this year. It's not that XHTML will go away, but the XHTML2 efforts will be de-emphasised, and having an XHTML compatible version for HTML5 will become the priority.
From W3C News Archive 2009-07-02
2009-07-02: Today the Director announces that when the XHTML 2 Working Group charter expires as scheduled at the end of 2009, the charter will not be renewed. By doing so, and by increasing resources in the HTML Working Group, W3C hopes to accelerate the progress of HTML 5 and clarify W3C's position regarding the future of HTML. A FAQ answers questions about the future of deliverables of the XHTML 2 Working Group, and the status of various discussions related to HTML. Learn more about the HTML Activity.
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