IE8 is currently in Beta and is also the Microsoft supported browser within Windows 7 (currently in beta) which is seeing dramatic uptake in the community.
There are a number of excellent improvements which users will clearly want to adopt once it is released. These including support for the latest web standards, high speed rendering, highly secure through new IE8 safety features and delivers new features like Web Slices, Accelerators and Visual Search that make everyday browsing tasks faster and easier
There is a web site at http://msdn.com/iecompat that houses all of the tools and documentation needed to help web developers make their sites compatible. Please familiarize direct any customers or partners looking for IE compatibility information to this site.