This is great news! Anyone who's spent time developing custom web parts for WSS knows what a pain it is to develop, test, and deploy them. Jan Tielens and the other guys at U2U made all of our lives much easier with the SmartPart v1, and now it seems they've outdone themselves! They have been working, with full support of the Microsoft SharePoint Team, to develop the SmartPart v2, or Son of SmartPart as Mike Fitzmaurice has pronounced it. This new SmartPart will allow WSS to host ASP.Net 2.0 web parts or user controls (with WSS SP2). Check out Jan's blog for more info!