How do I connect to a SQL Server Compact Database from SQL Server 2008 R2 Nov_CTP?

The database is present in the installation directory but you need to enable permissions.

Click Connect SQL Server Compact... in MS SQL Server Management Studio.

In the Connect to Server window click on the drop-down handle as shown.

Click on the drop-down item "Browse for more...". Expand the C:\node as shown

Click OK. The Connect to Server gets updated.
You may not be able to connect to the database as permissions are needed.

You can modify the permissions on the sample database. The database gets dispalyed in the Management Studio after you click OK on the Connect to Server window after modifying the premissions.