According to re/code:
Industry sources say Amazon is getting ready to launch a Web TV box that would compete with Apple TV and Roku’s line of products, which make it easy to move video from the Internet onto your TV.
People I’ve talked to who are partnering with Amazon believe the company is aiming for a March rollout.
I'm not so sure that this rumor will come true.
Yes, like pretty much everyone I too think that Amazon is working on a set top box; it makes too much sense for them to not have one in development. But I'm not convinced that said product is going to launch next month.
I don't know whether it's part of their marketing plan or not, but Amazon tends to leak badly before a product launch. In 2011 we knew a lot about the Kindle Touch and Kindle Fire, in 2012 there were quite a few leaks about the Paperwhite and the Kindle Fire HD, and last year we not only know what the Kindle Fire HDX looked like we also knew the codenames for all 3 tablets, the specs, and approximate prices.
How much do we know about the set top box?
All we have at this point are a few rumors that it exists, and that it runs Android. That's just not enough to convince me that it's going to hit the market soon. Until more information leaks, I don't plan to take this rumor seriously. It doesn't meet my standards for credibility yet.
Where are the photos? Where are the leaked details about price and features?
Heck, at this point the rumors don't even agree as to what this device will be able to do; some rumors say streaming video while others say gaming console. Sure, this could be the same device but why don't the rumors agree?
P.S. Does anyone think that it's possible this might be a SteamBox, one of those commoditized gaming console that Valve has been pushing over the past couple years, with Amazon as more of a content partner? This would fill Amazon's desire to get into the living room, and it would explain all the rumors as well as the lack of hardware leaks.