Basic HDTV's and the future of HD cable/dish signals?

[Teabaggins]

I have a pretty basic s4100(1080p)60 hz. the picture looks fantastic to myself and everyone else after some arduous tweaking with the limited color controls.

my question is this: 120 hz and other technologies are being pushed on some consumers as a way to solve feed problems from cable/dish services, right?

so is 120 hz just a marketing ploy? what are the benefits as I can't imagine anything looking better than what I have.

HDTV's magnify any weaknesses from their source(HD channels DVD etc) for the viewer.

I only see some pixelation in brief action sequences in movies on HD channels, never on blu ray or when watching sports unless the feed acts up.(I only watch action movies on BD anyway)

Dish and HD cable signal quality is only going to improve in the future, correct? so lag, blurring, pixelation etc won't be an issue at all for the more basic tv's out there now when the tech is at that level.

thanks for helping a noob out