Re: ROKU - Amazon Video On Demand (VOD) vs NETFLIX
Roku uses the Linux kernel, but it has a custom OS that is very different from a GNU/Linux distro, kind of like how Android is very different. I'm sure that since video is their sole purpose, they worked closely with Netflix and Amazon VOD to develop a custom version for their device, just like Android did. I'm sure that also includes paying licensing fees to the right people, which is included in the price of the device.
As for the completely different question you have in your title, I personally think that Netflix has a better selection available than Amazon.
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