I've been spending a fair number of cycles recently working with the pending update to BDD - BDD 2007. The major thrust of BDD 2007 is support for Vista deployments - but there has also been a good deal of time invested to enhance usability and ease of deployment.
A full discussion of the features of BDD would require much more space than we have in this entry but there are a few new pieces of BDD that are definately worth a mention. These include a new deployment workbench, a new configuration database and a new task sequence engine to control the flow of deployments.
The BDD workbench is configuration central for deployments. With the workbench it is possible to manage multiple OS images and combine them with application deployment, injection of required drivers 'on the fly', modifications to the user environment, control the individual steps of the installation, etc. Based on the configurations chosen the workbench will handle the required modifications to the various control files for you 'on the fly'.
The BDD database is new for the 2007 release and allows administrators the option of storing a library of configuration options in an online database. This database stores the same settings as would have previously been stored in the customsettings.ini file and allows the customersettings.ini to be generic across all deployments. Further, centralizing these settings in the database ensures settings consistency across all deployment points. These settings are then accessed by the BDD scripts during image deployment to read the various configurations requested.
Also new to BDD, the task sequencing engine, is actually techology borrowed from the upcoming release of OSD in SCCM 2007. The task sequencing engine is essentially a way to define, step by step, processes that need to take place during image deployment. These tasks could include customizations to the user environment, user or system state migration, restarting the computer, adding required applications, etc. Task sequences are very flexible for image deployments through BDD and/or OSD but also can be used as a basis for general deployments in SCCM 2007 - independent of BDD or OSD.