They are pretty cool,
here is a link. I have a couple of the cork pouches in other sizes and find them very durable and well done which is the norm for TB bags anyway.
Here is a thread about the reader pouch on the TB forums.
A couple nice things about the sleeve is, being a TB bag, it's pretty much water tight thanks to the outer material, layers and zipper. Next the sleeve has a clip so you can easily attach it to a handy ring or whatever inside or outside the bag you normally use.
Also, it does not look like it would contain anything like a reader device so it is sort of 'stealthy' in that aspect.
Did I mention the cork version will look GREAT?
I have several of the cork pouches already and love the look.
On the neg side it seems to hold the reader w/o it's cover and has soft sides so there might not be the protection to pressure or twisting the cover provides. Then again, when I do bother to use my K1 I remove it from the cover.
And yeah, it is just a simply variation of an existing pouch made by TB. But they did add the padding.
Oh, from the thread, the K1 does fit, sort of snugly but will fit. Gonna order one and will see how it fits. I think one of the posters also mentions their Sony Reader fits nicely as well.
I think it's a nice simple and inexpensive alternative in the cover/sleeve market for <= 6"-ish readers.