Site readability improvements

The current Jackrabbit site uses a relatively small font size (body at 10pt, navigation links at 7.5pt) and not much whitespace around key elements. I'd like to try changing these settings and perhaps use a serif font in the body text to see whether we can improve the site that way.

I'm no designer, so all feedback, suggestions and criticism is very much welcome. And I would love to hear more if someone with more design talent wants to give the site a more thorough facelift.