Microsoft's Patterns and Practices group released the latest update which is basically the final version of the current iteration. There's a ton of content there on helping people create LOB applications in and on SharePoint such as code samples, documentation and videos.
Check it out!: http://msdn.microsoft.com/en-us/library/dd203468.aspx
I was one of the contributors on the advisory board who helped in creating this fine resource... along with many others.