The Deployment Guys have a nice new post on using the Microsoft Bitlocker Administration and Monitoring tool.
Microsoft BitLocker Administration and Monitoring (MBAM) provides features to manage BitLocker encryption of computers in an enterprise. More information on MBAM can be found here.
BitLocker creates recovery information at the time of encryption and MBAM stores that information in the recovery data store. While MBAM can update its recovery data store when the agent is installed on a system that is already encrypted, it is preferable to have MBAM control the encryption process. MBAM Encryption is controlled by Group Policy. Group Policy is not applied during a SCCM Task Sequence. It is possible to have MBAM start encryption during the task sequence, the techniques are described in the following whitepaper Using MBAM Data Encryption With MDT http://go.microsoft.com/fwlink/?LinkId=229053