At MIX10 there were 3 SharePoint sessions. I went to each of the sessions and found all of them interesting.
All session links below go to the MIX page for that session. At the MIX page you can view the recorded session.
The session Designing an Internet-Facing Web Site Using SharePoint 2010 discussed branding, silverlight, and the features that enable SharePoint 2010 to support Internet sites. Among these features is Lockdown mode helps protect internet sites from anonymous access. It allows anonymous users to access SharePoint 2010 pages and sites but also protects pages in the _layouts virtual directory and the forms pages. This session provided in depth code examples for branding, theming, and even the incorporation of Silverlight elements to make sites more interactive.
The session Building Rich and Interactive User Experiences in SharePoint described the elements of SharePoint 2007 and SharePoint 2010 that enable the features that are necessary for public internet sites. Public internet sites need advanced branding and accessibility. Some public sites need translations for other countries or target users. This session focused mostly on describing techniques that could be used and did not cover actual code examples.
The final SharePoint session entitled Designing Corporate Web Sites using SharePoint 2010 described tools and techniques used to design sites in SharePoint. This is an interesting session as it shows developers techniques and the tools that support them like SharePoint Designer, Expression Blend, and Visual Studio. This session is a must for developers that want to build highly interactive sites in SharePoint.