HTML5 is not officially released yet but we are already seeing plenty of early adapters these days. There are plenty of viral blogposts trumpeting how ‘cool’ your websites can be with HTML5 (like this one, for example) but I don’t see many that talks on the impact HTML5 will do on search engines and SEO. To proceed, we need to first understand how HTML5 might change the way search engines look at a web page.
How HTML5 improves search engine’s understanding of the web?
Apart from being concise and able to create cool on-page visual stuffs, HTML5 improves communication between a web page and the machines (search engines, in our case).
New element in HTML5
First we have bunch of new elements like <aside>, <article>, <hgroup>, <footer>, etc in HTML5 that will help search engines to have better understanding on webpages’ segmentation*; which in turn, allow search engines to decide where to look for the main content and spending less resources in indexing less-important sections like footer and advertisement.
(*Side note: It’s no secret that Google can already do this for a lot of websites (blog especially) nowadays but it definitely will do better with the help of HTML5.)