MS CRM 2011 Beta - The NetworkCredentials provided were unable to create a Kerberos credential.

You might get the below error when trying to create a token for MS CRM 2011 Beta organisaion :

The application terminated with an error.
The token provider cannot get tokens for target 'http://192.168.1.99/XRMServices/2011/Discovery.svc'.

The NetworkCredentials provided were unable to create a Kerberos credential, see inner exception for details.
 
This is quite possible when you CRM is on Domain A, and you are trying to create a token from Domain B.

it's not going to work in beta currently. I believe there is an open bug for this. Hope it will get resolve in RTM.

See more information on the same:
Troubleshooting authentication problems with the Beta releases