I am not sure what Netflix gains content wise from buying AMC - they already have rights to Breaking Bad and Mad Men. Orange is the New Black and House of Cards both seem to be better received than any of AMC's new programming (Low Winter Sun is getting skewered by blogs/critics).
I agree that Amazon and Netflix are in the midst of the original content battle. Netflix is taking the analytical approach, whereas Amazon Studios seems to be scaling the typical production process to the web (scripts -> pilot -> pickups).
In the end, I think AMC needs Netflix more than Netflix needs AMC, so I don't see this kind of acquistion happening. But still a fun article to think about. Thanks for posting!
PS If you are interested in this kind of meta-TV stuff, check out Andy Greenwald's stuff on Grantland: http://www.grantland.com/contributor/_/name/andy-greenwald