They can try, but I don't see why people would adopt it.
Reason #1
Because it's fricking Amazon.
So people will buy into amazon's currency so they can spend it on Amazon? Might as well just vouchers. And any company can create their own money, but it wont be cryptocurrency.
If they did would it be 100% pre-mined?
Doubtful.
They'd probably "mine" it by offering rewards programs to get it into circulation. But it can only be spent on Amazon, issued by Amazon, etc. and might offer some value that cash doesn't, like "X amount off orders worth $Y" or expedited shipping, reduced sales tax, whatever.
Amazon likes to handle things in-house... they're the largest shipping operation in the history of humankind. Tens of thousands of outlets and warehouses. A whole internal system.
This kinda seems the opposite of what cryptos are about, but I guess it's only a matter of time before some corporation tries their own pre-mined Corporatecoin.
Oh, and YEAH, YEAH, YEAH!
http://blog.39degreesnorth.tv/wp-content/uploads/2010/10/bono_in_africasmall.jpg
No corporatecoin would ever be accepted by the masses or the media; not even Amazoncoin. After Overstock adopts btc, it is likely other retailers will follow. Another thread could be started on when Ebay/Paypal will accept. Bitcoin takes profit away from them so, actually more unlikely for EBay than Amazon. However, Online Retailers save money by using Bitcoin- - - No 1.5% payment to process creditcard plastic fees. This is big money & this is why online retailers will adopt someday.