For those of you who would like more control of your HTML output from ASP.NET 2.0, then check out the newly updated CSS Adapters Beta 2.
At one point I looked into using "CSS Adapters Beta 1" because the native asp:Menu HTML output does not work well with all browsers ( mainly Safari ). However, my direction was altered in another direction that didn't need the asp:Menu control, so Safari compatibility with the menu was no longer an issue.
Anyway, I know there are some hardcore CSS gurus who will do anything they can to not use tables for non-tabular data. If that describes you, or if you'd just like a little more control of your HTML output, then check out the CSS Adapters Beta 2.