On Wed, 18 Jan 2012, Javaheri-Ghazvini, Haamed wrote:
> Surprisingly, we've only encountered two Kindle OUIs in the last few 
>years-28:EF:01 and F0:A2:25. The latter is the more recent one with which 
>Fires appear to be associated.

Now that's very interesting. According to IEE, F0:A2:25 is registered to 
"PRIVATE". No corporation or agency, no address or anything.

Per: http://standards.ieee.org/faqs/regauth.html#3

The 28:EF:01 is registered to Diffon corporation in Korea. Presumably the 
company that makes the WiFi chipset in those particular Kindle models.

I don't see Amazon anywhere in IEEE's listing so it may well be the Private 
F0:A2:25 is dedicated to Amazon's use, though I'm not sure why they would 
want to hide it. With the Diffon Corporation, they own a ton of OUI space so 
you may get non-Kindle devices that that OUI.