I can confirm that they are indeed out and available at Best Buy. I first saw the Slim Book out at my local Best Buy Thanksgiving Evening (when they were doing their early Black Friday sales). They're currently listed for $129.99 just like on ZAGG's site. The reason why no one can find the SKU or listing on Best Buy's website is because Best Buy has them INCORRECTLY listed as the ZAGGfolio Bluetooth Keyboard Folio Case for iPad Air 2. Here is the link:
http://www.bestbuy.com/site/zagg-za...lack/9877103.p?id=1219443110041&skuId=9877103
I bought both the Logitech Tye+ for iPad Air 2 and the Slim Book to compare and see which one was better. I preferred the Logitech Ultrathin above all, but unfortunately, the tempered glass screen protector I use on my iPad Air 2 makes it a hair or two thicker for the magnetic slot.
The Slim Book has fairly good build quality. The bottom keyboard portion is made of aluminum, while the underside is made of fairly hard plastic. The case that attaches the iPad is made of incredibly brittle and thin plastic that I fear will not be as durable in the long run. However, this design does allow the added convenience and flexibility to attach and detach from the keyboard. The keyboard itself is nice. However, compared the Logitech, the key travel is shallower, and the keys themselves are smaller than the ones on the Logitech. I found that the Slim Book also required firmer keystrokes to ensure output as I often found myself typing words with missing letters.
The Logitech Type+ has a far more solid build quality with soft touch and grippy nylon. Despite lacking premium materials and features like aluminum and a backlit keyboard, something I found myself not mising all that much, there's a sense of durability that I didn't find in the ZAGG Slim Book. The keboard is more widely spaced and far more comfortable to type on. The folio itself does not add any more thickness nor bulk than the ZAGG. The magnetic lock on the Logitech is also far more secure, and because of the folio's folding design, the iPad does not wobble when the screen is touched. The ZAGG's hing mechanism is incredibly rigiid, so it appears the iPad slot is the culprit when it comes to the wobbling issue.
Overall, I think I'm going to return the ZAGG Slim Book and keep the Logitech Type+.