I am loving Suffusion! I have never seen this much functionality in a WP-theme!
There is a problem though, otherwise I wouldn't be posting ;-)
When I add a 'search' widget to my page (www.martijnboersma.com) either in the left or the right header widget area, a grey bar is created that spans over the entire width of the page. I have noticed that this bar is absent/transparent on other sites that use the suffusion theme (www.dejaap.nl), even though they have the 'search' widget in the right header widget area.