I saw the case at left in a bunch of booths at CES, and ever since then I've been waiting for it to pop up on the market. A few days ago I came across this case on the Walmart website.
The case is designed to fit most 7" (800x480) tablets; the clips on the top and bottom are adjustable. It would probably also fit the NookColor or anything with that general shape. (Note that this probably won't work with the NC; I don't think it has USB Host.) It's an 84 key Keyboard and it has a standard USB port.
Mine is coming in the next couple days, and I will be posting a review.
But wait, there's more. now that I new it had hit retail, I kept digging and eventually found a Chinese retailer that carried it. They have this style of case in 3 different sizes (7" 8", 10") as well as an iPad case (and a lot of other junk).
They also posted a demo video which shows a lot of detail.