An interesting 2 part article has just been published by Patrick Tisseghem of U2U, on writing custom code for Widows SharePoint Service 3.0 which is the underlying technology to MOSS 2007.
Here's the summary of the article:
"Learn the skills you need to develop for Windows SharePoint Services 3.0, about the differences from traditional ASP.NET development, about the required development environment, and the steps to build a Windows SharePoint Services solution with Visual Studio 2005 Extensions for Windows SharePoint Services 3.0."
Part 1 can be found at this URL: http://msdn2.microsoft.com/en-us/library/bb530302.aspx
Part 2 can be found here: http://msdn2.microsoft.com/en-us/library/bb530301.aspx
Although I have not yet read the articles myself, they have come highly recommended by Mike Fitzmaurice who was formerly the Senior Technical Product Manager for WSS/MOSS development and integration. That being the case, and the fact that WSS & MOSS is becoming a very popular Application Platform with Web Parts, Workflow and custom ASP.NET pages, I thought that I would get the news out now to our blog readers and I plan to read the articles myself later this week.
~ Robert Shelton