The future of HTML is HTML 5. Rest in peace, XHTML 2.
This said, the <video> tag in HTML 5 is pretty much dead on arrival too. Check Video for everyone for an interesting attempt at reasonable fallback. I say Flash is far from dead yet (which is, for the Mac users at least, too bad).
I also do hope that the <NSFW> tag never makes it in HTML 5. This is highly cultural and sensitive. Pretty much nothing is not safe for my work — actually I think the divide should be between legal and illegal content as far as I'm concerned, and that even is highly variable if not controversial. Who are you to slap a moral judgment on content? Leave your puritanism out of my web! And if you need someone you don't even know to slap a Not-Safe-For-Work-You-Idiot censortag so that you can safely and randomly surf the interwebs from your office open space, I suggest changing job. Merde alors !
I was surprised to hear that XHTML is being dropped in favor of further development of the HTML standard. That's interesting news.
As far as the NSWF tag goes, give me a break! That's ridiculous. Maybe we should introduce a tag too, then?
NSFW was a joke and I'm surprised that people started so quickly on this. Ah, the mysteries of the interweb! ;)
On the other hand have a look at the LONGDESC attribute which, although useful, may go the way of the dodo if no more people complain.
As depicted by Jeffrey it didn't look like a joke. I prefer it that way then :).
The LONGDESC attribute seems useful, why remove it?