As I learned from Patrick's blog this week, Jan Tielens of U2U has written a comprehensive overview of Sharepoint web parts on the MSDN Belgium site entitled Web Part Platforms and Development Techniques. It's a nice history of web-part development that explains the options for Sharepoint 2003, .NET 2.0 and Microsoft Office Sharepoint Server 2007.
Patrick and Jan helped us put on the Office "12" Ascend workshops earlier this year, and they did a great job. As did Ted Pattison, who has a new Sharepoint training firm called Gorilla Training. These guys are all world-class trainers on Office-related technologies, so check out their web sites if you need developer training for Office or Sharepoint: