Is 1080p via DirecTV

I've been wondering.. I realize that there are several possible broadcast formats with digital television, but since the ATSC digital television specification does not include 1080p as a part of the HDTV standard, how can satellite and cable providers now offer this resolution? Is it just marketing hype to ride on the coattails of Blu-ray?

By comparison, it would have been unheard of back in the days of NTSC for a broadcaster in North America to use anything but the then-standard 480i NTSC signal. Am I missing something here?