I don't have cable at all, and I live overseas. So Prime is a major source of entertainment, both via their free video content, and their free Kindle rentals. Additionally, I do much of my shopping via Amazon for things that I can't find here (and though some people say it hasn't worked for them, my Prime subscription carried over to Amazon.de so I can use it on both sites). Of course, if you are typically spending more than $25 (?), then most shipments are free anyway, so that's something to consider.
But for me? I save that $79 probably 3x over at least.
Oh, and if you aren't going to use the streaming content, sign up for Amazon mom. (Anyone can do it; I am not a mom.) It's free for 3 months, I think, and then it is extended each time you purchase qualifying items. Depending on your shopping habits, you might get some extensions. (Again, it isn't all baby and kid stuff, though most qualifying items are. I got a couple extensions for things like a new pizza cutter and some underwear.) If nothing else, it's a few months free, allowing you to hold on to that $79 a little bit longer.
My Mom membership didn't give me access to the free streaming content though.
