It's no secret, troubleshooting ADFS can be tough. That's why a few key members from our ADFS Test Team (Krish Shenoy and Marcelo Mas) took it upon themselves to create a diagnostics tool that can make troubleshooting ADFS much easier. I am inserting an image of a flyer we created recently (just click the image to see it expanded) that explains what the tool does and how you can use it. I am also inserting a couple of links below since they don't show up hot when you click on them in the image. Enjoy!
Where to get the tool - http://blogs.technet.com/adfs/archive/2007/11/01/adfs-diagnostic-tool.aspx
Where to send feedback - http://blogs.technet.com/adfs/default.aspx