A Hyper-V virtual machine has been made available by Microsoft which contains SQL Server Denali CTP3 + SharePoint 2010 + Office 2010.  I downloaded each part, extracted them, imported my VM, and launched it for the first time with great anticipation.

Then things came to a screeching halt:  Cannot connect to the configuration database.  This message was displayed when I tried to launch the "SQL Server - Home" link on its desktop.  Central Admin had the same error.

To resolve:  go to Services (Start > Administrative Tools > Services) and start the SQL Server service for the POWERPIVOT instance.  Although it's set to be automatic, it's apparently not.

Also, I found I needed to restart the VM twice.  If starting the SQL services doesn't work for you & you've only rebooted once, try one more reboot + starting of the SQL service.  That sequence of events worked for me.