Perhaps a negative correlation.
If you assume that most of those people live in rural areas, you have to realize that it is MUCH harder for them to get broadband than it is to get a blu-ray player and blu-ray discs. You are apparently trying to say that these people are behind on technology in general, and I really don't buy that... atleast not to the extent that you do. Are you saying that the percentage of people in rural areas with a DVD player is less than those in urban areas? I think the difference is negligible.
To get broadband there would need to be a company which considers it monetarily viable to add service to their area... which is unlikely. To get blu-ray, they just need to get the mail (everyone in the U.S., UK, whatever) and have a Wal-Mart or other electronics dealer in there area. The retail saturation is much higher with Blu-Ray than with digital download mediums... obviously.
On the other hand, I personally feel that the war between Blu-Ray and HD-DVD left an opening for digital downloads... and I think it is the wave of the future. I will maybe never own a Blu-Ray player for this reason. To me, physical media has next to no appeal... other than to rip content to my computer.
THX Scientist says it's too late for Blu-Ray
I was assuming a few things. First, I was spotting you on the broadband adoption rate at 40%. Then, I was assuming that of the 60% left, that most of them could have it if they wanted to. Does 60% of the US live in rural areas outside the reach of broadband? Does even 30% I doubt it. I may be wrong though.
Secondly, I was assuming that people who live in rural areas are generally less techie oriented than urban areas. No real evidence for that again - just an assumption. But it seems like a reasonable thing to me. I just don't picture most farm houses being decked out with an 1080P HD TVs and satellite dishes pushing HD to their TV (and having VOD for HD movies, BTW, from the dish companies), and then sitting around tapping their foot waiting for blue-ray to get affordable and be available in the new Mac that they want.
I think this next gen HD optical shot itself right in the foot.