Quote Originally Posted by rsteven View Post
Ok so as I am about to spent alot of time becoming proficient at coding strict standards compliant websites what do you recommend I learn?
HTML 4.01 Strict (plus CSS 2.1 and DOM Level 2).
It's the latest recommendation that is reasonably well-supported by contemporary browsers.

Quote Originally Posted by rsteven View Post
However deep down I feel like I will be missing out on something cool if I leave off the x :-)
Believe me, you're not.

Quote Originally Posted by rsteven View Post
...also I am planning to build alot of sites, perhaps a few hundred so if I go for XHTML but served as html would that be better in the long run? I could essentially change the way my pages are served to proper XML.
It won't be better in the long run, but of course you can do it if you want to. Before you do, though, make sure that you really understand the profound differences between XHTML and HTML and study Appendix C of the XHTML 1.0 specification very carefully.

Quote Originally Posted by rsteven View Post
This way would I have more chance that the websites would be more future proof?
No. If XHTML ever becomes useful, it won't be XHTML 1.x but some other version. It will most likely not be backwards compatible with HTML or XHTML 1.x, so you will have to rewrite your documents anyway if you want to 'upgrade'.

Quote Originally Posted by zcorpan View Post
Actually it doesn't; it requires support for either XSLT and HTML, or XHTML (supporting both will work fine, too).
You're right. If the xml-stylesheet PI isn't supported, it will be handled as XHTML.

Quote Originally Posted by zcorpan View Post
Firefox 3 will support incremental rendering of XHTML (in the general case, at least).
Living in the future as always.
HTML5 will do this … CSS3 will provide that … Firefox 3 will support the other …