For a very long time, DIRECTV HD users have had to build their own distribution systems to share receivers and DVRs via RF modulators. During that entire time period, DISH Network offered their two TV solutions with built-in modulators.
What we're seeing with DIRECTV's WHDS is a leap-frog over DISH's technology to a peer-to-peer setup.
It remains to be seen whether or not DISH Network can beat DIRECTV to the true Whole Home DVR (client-server) punch. It is looking like a very tight race with both hinting at general availability early next year.
DISH had a single wire solution for DVRs at least two or three years before DIRECTV finally bowed their SWiM technology that leapfrogged what dish was using.
Take a look at all the "innovations" that DIRECTV promised at the mid 2000's CES shows and see how many of them just didn't make it. I think you'll find the list at least as long as the list of DISH features that fell short or didn't show.