This is a question that has been answered in a number of different places. Unfortunately, the answers in some instances have not been good ones. In fact, they’ve either been way too optimistic and/or presumptuous — or else just downright wrong.
Also, when we use the term “HTML5″, what exactly are we referring to? HTML5 covers a number of different features and technologies, some of which have nothing to do with SEO. So, generally speaking, when people ask this question, they’re usually referring to HTML5′s new semantic elements. So, I’ll primarily focus on those here.
What Do Other Sources Say?
As mentioned, a number of blog posts have tried to answer this question. Here are a few examples:
To put it quite bluntly: They’re wrong. No, they’re not 100% wrong; I would never say that about any article. But there are things stated in those pieces that are somewhat misleading and presumptuous. Not to mention that a few of them have some blatant errors. The reason I point these ones out specifically is because they come up early in search results for HTML5 and SEO.
Of course, the somewhat shady nature of those sites should tip most people off to their less than authoritative voice on this subject.
Will HTML5 Help Your Content Rank Higher?
Using HTML5 semantic elements in your pages today will not give your content higher search engine rankings. And I would venture to guess that the semantic elements will never have an effect on page rankings. In fact, it’s almost ridiculous to think this would be the case.
Even if there were eventually some small benefit added to Google’s ranking algorithm for the semantic tags, the difference would be so small that it probably wouldn’t matter. Although we don’t know, and probably will never know, how Google ranks pages, we do know that two of the most important factors are relevancy of content and quality backlinks. And that should never change. Trivial use of semantic tags should never affect SEO rankings, and they certainly don’t do so as of this writing.
Although there may be some more up-to-date sources on this subject, here are a few relevant Google Webmaster Central posts that address this or related issues:
The answers to each post are provided by Google employee John Mu, so unlike some of the overly-optimistic posts cited in the previous section, these are worthy of consideration.
You might also be interested in reading this article on HTML5 Doctor for further info on this subject.
HTML5 Can Help Categorize Content
But even in this case, Microdata will not boost your SEO ranking; it will simply make specific parts of your content have more semantic value, making it easier for search results pages to compartmentalize and display your content to users. You can get more details on this subject on this schema.org FAQ. This concept is similar to Google’s rich snippets, but schema.org seems to be a more powerful replacement for rich snippets.
Don’t get too excited about any potential SEO benefits to using new semantic tags in HTML5. The fact is, a website built with HTML tables that has relevant content and quality backlinks will easily outrank any site structured with HTML5 semantics that has poor content and few backlinks.
So be realistic about HTML5′s benefits. Semantic tags are not a magic bullet for higher Google rankings, and probably never will be.