MMC is the result of Microsoft's effort to create better tools to administer Windows. The Windows administration development team defined a common host for many of its own tools. The MMC project's initial goal was to support simplified administration through integration, delegation, task orientation, and overall interface simplification - all key customer problems.
As Microsoft addressed that goal, it increased the project's charter to include all Microsoft administration tools, and to offer this generalized framework for management to its many ISVs as well.
MMC is a core part of Microsoft's future management strategy. Most Microsoft development groups will use MMC for future management applications.