Nothing sinister, it is reallocation of bandwidth. The DTV bandwith allows for better TV signals with more data for those, while the existing bandwidth that analog is running on is actually more ideal for communication, specifically a unified emergency communication network. It also opens up that bandwidth for other telecom carriers to offer more advanced services.
Yes advanced services like parking meters that send your violation to headquarters automatically.
There is actually more to it than reallocation of bandwidth. It includes digital rights management (DRM) capability. The digital signals can be encoded so that they cannot be recorded for later use. This is the same technology that has made MS Vista so popular. [end sarcasm]