Hello HTML 5!

In need of some touch ups, I started a redesign of this site (http://www.danux.co.uk) a couple of days ago. I thought it might be fun to give HTML 5 a go, so here it is!
I've had a pretty mixed experience, while the coding was pretty simple, and made a lot of sense, I'm about the go to war with browsers to get the site rendering correctly every where.
Internet Exlporer won't play nice at all, the navigation is broken, as well as the "Keep Current" alignment. Firefox 3.5 is having problems too, and Firefox and Safari cannot agree on how to absolutely position things. Opera seems to be quite anti-sprites.
Other than that though, its all good. Next I need to rewrite some of the copy on the site, write the new "work" section, and try to brigten things up.
Have you had a go at HTML 5 yet and how did you find it? What's holding you back if you haven't?
re: Hello HTML 5!
This might be of use to you regarding IE and HTML5 as IE needs to know an element exists before it can put styling on to it.
http://remysharp.com/2009/01/07/html5-enabling-script/