A Google Webmaster Help thread has one webmaster asking if it would be a bad thing for him to use block-level links in his HTML5 web site.

First let me explain what it is by referencing HTML5 Doctor:

Google’s John Mueller kind of cautioned against using this technique. He wrote:

In short, since the whole paragraph is one big link, there is a ton of anchor text to associate to the link. So it may be confusing for Google to understand what that link is really about.

Forum discussion at Google Webmaster Help.