Web CMS vendors, web developers, and web UI component developers will likely be getting some exciting new extensions with the proposed changes in HTML 5. Think <datagrid>, <canvas>, and a richer set of native HTML form widgets.
XHMLT 2.0 should lead to greater device independence, simpler and more generic XML, less presentation, more structure, more semantics.
The Ajaxian blog
has some interesting coverage, links to current proposals, and links to recent talks and presentations.