This is an interesting concept, but what caught my attention is the observation on how as technology evolves the individuals items on the gradient move along the axis as a consequence.

"Often technology helps us to organize the priorization, or to move a medium along the push/ pull axis… for instance, a tape recorder pushed the radio from push towards pull some decades ago (e.g. a tape you’re playing can handle interrupts – unlike radio, you can pause the tape during an incoming phone call). In the other direction, a website can turn into a blog to move a bit more towards push, and it can move further towards push when people use a feed reader to digest it."

I’m not sure if a product concept is being revealed or just thinking out loud. At any rate, I am finding myself wanting to have a "broker" for the various services and communication tools I use, but only if I can define the prioritization and rules, so the push vs. pull gradient is a good way to look at it.