A visual representation of the differences in how Gecko browsers (Firefox, Camino) and WebKit (Safari, Shiira) handle images that are not in the sRGB color profile. WebKit can read the ProPhoto color profile, while Gecko and IE cannot, giving the photo that undersaturated, washed out look. A few of my more recent flickr uploads are in the ProPhoto profile, so if you view them in Firefox, you'll see a less-than-stellar color palette.
Update: I went back and replaced all of the troublesome photos. The web has standardized on sRGB and most monitors don't benefit from other profiles anyways, so it doesn't really make sense to work in anything else unless you're picky and you make prints.
"Shiira is a web browser based on Web Kit and written in Cocoa. The goal of the Shiira Project is to create a browser that is better and more useful than Safari. All source code used in this software is publicly available."