HTML still has it's applications, but if you want maximum results in design, functionality, ease-to-upgrade and browser compatibility - and be search engine friendly, you NEED to use CSS.

hmmmm I've actually found:

CSS Layouts take a little longer to load:
because it has to load a single HUGE stylesheet, a javascript for workarounds and monitor resolution monitoring....because it's not truly and completely cross browser compatible

I'll give you that CSS is compatible with all browsers. However, not all CSS is compatible with all browsers, and you end up having to pack the CSS stylesheet with more css code to make it work, or include a large js javascript include to provide conditional workarounds.

Additionally, when resizing a css layout, you tend to get overlap of divs, etc. things don't line up the way they're supposed to.

Additionally you don't "NEED" css to be search engine friendly. You need proper use of content, code, and meta data, and link backs don't hurt either.

In my day job we used css to merely style the page. the rest is HTML, and when the new site launched on Oct 15th, we increased our readership from 5,550 per month, to 434,000/mo. Not too shabby for a non CSS layout eh?

Of course you don't NEED css to be search engine friendly. You do NEED proper use of content, code and meta data, plus revelant back links. An awful lot depends on the complexity of your site, it's functionality and purpose - as to rather HTML alone is the answer. More often than not, CSS/HTML is the better fit.

And congrats on the success of your non-css site, ANMark.

I find that a smart hybrid of the the languages and methods available...html, css, javascript, etc, are the best way to go.

We live in a brilliant world where limiting one another to one thing because it's "popular", is also limit one's creativity. Who know what someone will come up with by thinking outside the box?

I suggest you to learn both, CSS is way better for coding designs.