It’s difficult to get a definitive answer when you’re asking for people’s opinions!
My view is that, unless you are going to make use of other XML technologies that can’t be integrated into HTML, there is no advantage in using XHTML over HTML, and there’s more work involved. And you can’t do that unless you want to make your site an IE-free zone, which means that in practical terms there is no reason to use XHTML.
Yes, use the Strict doctype, and yes, close all your content-containing elements. But having to close spot elements is nonsense. Why is the construction <br></br> helpful, given that it can’t contain anything? It isn’t - <br> does the job just fine, it’s unambigulous and it’s much harder to get wrong, so use it, and don’t make life unnecessarily complicated for yourself.
There are articles which say that if XHTML is served as “text/html”, then it is seen as “Tag Soup” - so don’t use XHTML. Then there are some others that say it is NOT wrong to use XHTML, just use the “strict” doctype.
I think fauXHTML and tag soup are different things. All that fauXHTML means is making your spot tags self-closing (eg <br />), whereas tag soup is when your code is a complete mess - particularly when you have presentational markup but also when you have squillions of <div>s that are completely unnecessary.
Q: Now that XHTML is dead (as of December 2009), should we at all use it?
Who says that XHTML is dead? XHTML5 is in development in parallel with HTML5.
Q: Is it OK to let browsers see our markup as Tag Soup - i mean from the “Best Practices” viewpoint?
You should always avoid tag soup as far as humanly possible. Tag soup describes bad code, so it’s pretty much guaranteed that anything that can be called tag soup could be done better some other way.
Q: What if we completely abandon both HTML 4.01 and XHTML, and start using new HTML 5 with its new simpler doctype? (Two popular websites I know of, that currently use HTML 5 are Google and LinkedIn)
I’m not sure how you plan to “abandon HTML 4.01” and use HTML 5 … pretty much any code that’s valid as HTML 4.01 Strict is also valid as HTML 5!
Or if you just mean change the doctype, I don’t see any reason why not. I haven’t got round to thinking about that yet, partly because I don’t see any need to, but equally because the doctype is hard-coded into each of the 1000+ pages on my main website and I can’t be bothered to change them! Why don’t I think it is worth using HTML 5? It is only worth using the doctype if you are actually making use of HTML 5 features - and support for those is still somewhat flaky, so you’re in danger of making a site that doesn’t all work properly in some browsers.
And as for Google - Google is not an example of good practice!
Q: I don’t understand how HTML vs XHTML depends on the web page at hand - i mean how and in what ways a web page can dictate whether HTML or XHTML is right for it?
Leaving aside the unlikely issue of using genuine XML technology, whether to use XHTML or HTML comes down to authorial preference. What’s on the page shouldn’t make a difference, and if anyone says it does then it is almost certain that they are using ignorance to justify their own preference.
Q: Isn’t using XHTML all about author’s yearning to write strict markup, to always use “Best Practices”, to always use “latest & greatest” technology?
When I see people exhorting the use of XHTML, my first thought is “Can anyone say ‘bandwagon’?” … and that has been my view for about 10 years. But what once looked like a bandwagon to be an ‘early adopter’ now looks like it’s become a runaway train. IE’s complete inability to use XHTML properly has scuppered the potential benefits of XHTML (which, even if we could use it as XML I think are pretty slim and would not be relevant on any of my websites). Now a lot of people use XHTML because they think it sounds better than HTML, and it’s got more buzzword cachet. The problem with being an early adopter is that sometimes you back the wrong horse.
Q: Can’t we use normal HTML 4/5 with all the “Best Practices” that we learned for XHTML?
<barack obama>Yes, we can!</bob the builder>
[Q]: Can I draw this conclusion:
“DO NOT USE XHTML, just use HTML 4.01 Strict, or new HTML 5 with known best practices of XHTML”
Sounds fair to me 
