This is correct.
And until officially announced we can just guess, this rule could just be for new customers and not existing ones.
Are you certain Dish didn't mean 6 LEASED tuners, and after that the customer can pay full retail. Is it not now (changed about a year ago) a limit if 6 LEASED tuners, and more the customer can pay for? That would seem consistent, unless you are saying Dish will not allow more than 6 tuners in any household? Up until about a month ago, I had 12 tuners for a very long time, Dish leased by the first 4 tuners, but I paid for the remainder.
I can see a few family situations such as many generations of families moving in together because of the stinky economy who might really use a 3rd Hopper for 9 tuners, but it would be certainly be reasonable for Dish to expect the customer to pick-up the full tab on any Hoppers beyond the first 2. Of course, Dish will have to limit the number of Hoppers it will allow in a household for a while so they have sufficient inventory to provide them to as many households (especially new) as possible.