The Ape,

I suspect the differences you noticed in the search engine inclusion were due to some other factor. With all due respect, I have not seen a difference in HTML vs. XHTML as to whether a site was indexed quickly by Google.

I use a content management system that does not output all valid XHTML. The code I personally add to it is valid. But the code wrapper around my code by the CMS is not completely valid. And it's a bit bloated, too.

I think Google is just indexing sites faster now. My sites show up within a few weeks. It used to be the case that I might not get indexed at all, but that was a few years ago. Or maybe it's just that my content is better now?

I bet your content is better now too and that you are doing something else different.

Something I believe makes a difference is that, since I use a CMS, my content is updated frequently and is much more relevant and there's more of it, since it's easier for me to add content. And all that helps my search ratings AS WELL AS getting my site indexed in the first place.

In the past, I would register a domain name and then it would sit for months, with no or little content or updates. Now, I get content up the day I register the name, which has propogated quickly so my site is literally available in less than 15 minutes! Of course it helps that I own my hosting company, so I create an account, register the name, upload content, and 15 minutes later ... a live Web site, ready to go. Shortly thereafter, within a few days usually, Google hits my new site, which already has content. As the site develops, more content is added regularly. So each time the Google bot returns, there's plenty of new content

I think all that makes a huge difference, not whether the content is coded in HTML, XHTML, valid or not.

Does any of that ring true for you? I would be very interested in hearing more about your experience.