I dig the Top Sites feature. I arranged each row (more or less) for a different class of site, blog, news, forum, work, etc. Hopefully in the future the thunbnails will update more often and will authenticate on sites automatically to get a proper thumbnail.
A broader comment on Apple's visual design: I enjoy spending my considerable time in front of a computer in an elegant and visually pleasing environment. I'm not sure it makes me anymore productive but it definitely makes things more comfortable working on a long project. A big factor is the participation of third party developers. They generally stick within the overall idea that apps should look good, be somewhat minimalist in their functionality, and fit into the OSX way of doing things. It's a much less disjointed experience than using Windows or Linux.
I fully expect blogspot to fuckify this image so: