The previous versions of XHTML, XHTML 1.1 and 1.0, were made to be pretty much compatible with HTML 4.1. The problem with this was that it left a lot of presentational information in the Document Type Definition (DTD). Using the <b> tag says that you want to make a certain piece of text bold. However, the idea of XHTML is to separate content and layout. Therefore, all presentational aspects of XHTML are completely gone in the upcoming 2.0. There is no “Transitional” or “Frameset” DTD—both concepts are gone… XHTML will include no presentation, requiring it all to be defined using CSS.
I read this, and it makes me giddy. *insert nerdy snort* This is an excellent introduction to what is coming in XHTML 2.0 and how web design is going to change drastically when it arrives. Very cool stuff coming in the future.