What is changed in SCCM 2007?

There have been several changes from SMS 2003 to ConfigMgr including:

Feature Packs that used to be separate add-ons in SMS 2003 are now incorporated into the core ConfigMgr product (for example the Administration Feature Pack, Device Management Feature Pack, Operating System Deployment Feature Pack Update).

Improvements/ enhancements to Feature Packs include:

Operating System Deployment (OSD) - Images created in Windows IMage (WIM) format can be deployed (including any required applications), using bootable media such as CD/ DVD. One or more tasks can be created and combined to create a Task Sequence to control and customise the deployment of the image and Software Distribution actions.

Mobile Device Management - The ability to manage Windows CE and Windows Mobile devices in the same way as regular ConfigMgr Clients (such as Hardware and Software Inventory, Software Distribution, Software Updates, and of course Windows Mobile settings).

Transfer Site Settings Wizard - Allows the settings from one ConfigMgr Site to be transferred to another to save the admin having to reconfigure the settings on every Site. Settings covered by the wizard include Client Agent configuration, Discovery Method configuration, Package and Collection properties amongst others.

Manage Site Accounts Tool (MSAC.exe) - A command line tool used to create, list, verify, update and delete user-defined accounts for use by ConfigMgr.

All Site Servers and Site Systems must be a member of an AD Domain.

Primary Sites only support Windows Authentication for the Site Database.

Asset Intelligence introduced as an optional component in SMS 2003 SP3 is now included in the core product.

NOTE: As a result of the above two changes the core product requires a greater amount of server resources.
Major changes to the way Backup and Recovery works - Volume Shadow Copy Service (VSS), available with XP, Windows 2003 and later OSs allowing a capture of a ConfigMgr Site to be made and stored on other media.
Improved Remote Tools integration with Remote Desktop and Assistance - RDP is now used to communicate with XP, Vista and Windows 2003 (or later) Clients (Windows 2000 machines use a modified version of the SMS 2003 Remote Tools Client Agent). Remote Reboot, Chat, File Transfer, Remote Execute, Ping and Windows 98 diags are no longer available in ConfigMgr.

Minor improvements to Collections, Software Distribution and Software Metering compared to SMS 2003.
Senders can only now be installed on Primary or Secondary Site Servers.

Only one Client type (basically the SMS 2003 Advanced Client so no Legacy Clients).

Only a single Security mode (similar to SMS 2003 Advanced Security mode).

The Site Server's local boundary is no longer automatically configured as a Site Boundary - you need to define this post installation.

Site Boundaries are no longer supported - only Roaming Boundaries are with a choice of "Slow or unreliable" or "Fast (LAN)".

Client Push uses the Site Code of the Primary rather than being set to "Auto" as in SMS 2003.