Update: Now that I have the Aura HD in hand I am convinced the rumor is true.
My source was quite firm on both the number of screens made and the fact that B&N passed on buying them. I have not been able to verify either part of the rumor, but I do have a few facts to flesh it out.
E-ink makes the screen (obviously), and in the case of the 6.8" screen E-ink can assemble the entire combined unit (frontlight, touchpanel, and E-ink screen) and sell the screen as a unit to Kobo or anyone who wants to buy. E-ink tells me that this screen is in production at the moment and that it is available to Kobo's competitors.
On a related note, this ereader showed up on the FCC website in March and was originally tested in February of this year. No, I didn't see it at the time and I am still kicking myself for that.
Assuming this rumor is true, when do you think B&N decided to pass on the screen?
Here's my speculation.
First, I find this rumor plausible because Kobo doesn't do Spring launches; the Aura HD launch came as a shock. Also, Kobo released their newest devices only 7 or 8 months ago so releasing another new device this soon was a double surprise.
But as for B&N, this could not have been the screen that B&N wanted on the Nook Glow; that was far too long ago. That ereader would have had to have been finalized in February or March 2012 so it could hit the market in May 2012.
That suggests this 6.8" screen would have had to have been intended for the next model, and I think I can show that B&N would have been interested. Last Fall B&N revealed a marked interest in cutting edge screen tech. The Nook HD had a higher resolution 7" screen than anything on the market. Ask any reviewer and they'll say that it's biggest issue was the B&N lock-in, but other than that it had all around impressive hardware. What if B&N was planning for their next ereader to be similarly impressive?
If you find that plausible then I'm sure you'd agree it's entirely possible that B&N was also quietly funding the development of a high resolution E-ink screen in preparation for a Spring launch.
We didn't see that screen last Fall because B&N has a policy of only releasing new Nook ereaders in the Spring (May or June). That's when they released the Nook Touch and when they released the Nook Glow. Furthermore, this policy was confirmed to me at the Nook HD launch event last year.
Only now I don't think they will - not this year.
It's my guess that, assuming this rumor is true, B&N passed on the 6.8" screen as a result of the disastrous holiday season. Take this a step further and we see that they might no longer be investing in new hardware.
To be completely honest, I hope this is not true. A new cutting edge ereader would have changed public opinion about B&N and it could have revitalized the Nook platform.
But is this rumor true? I don't know, but I tend to think it is. It just fits too well with the facts I do have, though I cannot prove the connection.
I contacted both E-ink and Kobo, and held this post until I heard from one of the companies. E-ink sent me a politely phrased no comment (and answered some technical questions), which I won't quote here.
Kobo has yet to respond. TBH, Kobo has only responded to my press queries twice since July 2012 (I'm not kidding), so I was not surprised to be ignored once more.