I've used Paul Irish's boilerplate and I can attest that even if you decide not to adopt it outright, you can learn a lot just by reading through it.
HTML5 is one of those ever-changing technologies where what was once considered common-practice is now considered deprecated. I think this is often the case with a fast-moving, widely distributed technology. Paul does a great job of collecting a lot of wisdom and maintains it in an easy to understand format. It also does backwards compatibility right. Helped me out a lot.
I love the idea of being able to do a
git merge html5-bilerplate html5bp-test-upgrade
into one my projects and pickup the latest best practices to review. In practice I've never done that and I hand pick the parts I want.
Paul Irish's projects (and his cohorts) do a really good job of exposing the current state of web technologies. The Modernizr docs for example talks about how many JS and html5 apis are supported differently and what you can do about it.
HTML5 is one of those ever-changing technologies where what was once considered common-practice is now considered deprecated. I think this is often the case with a fast-moving, widely distributed technology. Paul does a great job of collecting a lot of wisdom and maintains it in an easy to understand format. It also does backwards compatibility right. Helped me out a lot.
Edit: Also he's a really nice guy. :-)