Please download SPGDrop20090424.6.exe and follow the setup instructions in "Setup and Validation.docx".
Please read the "SharePoint Guidance V2 Reference Implementation Overview.pdf" for the reference overview.

In iteration 8 we addressed the following areas:

• Exception Handling
  • Exceptions in web parts (ProductDetails and Pricing web parts)
  • Exceptions in list item receivers (IncidentTaskReceiver.cs)
• Site Directory
  • Updated Subsite creation process to use site directory (PartnerSiteDirectory.cs)
• Refactored AJAX Support project to use SPWebConfigModification instead of declarative approach
• Created LOB Service Support project to deploy web.config modifications required for LOB services
• Refactored ServiceLocator out of the Contoso namespace and made it more general purpose

Here is a blog post that describes the post in more detail:
http://blogs.msdn.com/erwinvandervalk/archive/2009/04/27/sharepoint-guidance-v2-drop-8.aspx

And the video for this iteration can be found on Channel 9:
http://channel9.msdn.com/posts/akMSFT/pp-SharePoint-Development-Guidance-v2-Whats-in-Drop-8/