But Greenwald carefully timed, well marketed, and over-hyped releases are equally as obnoxious. Of course they are going to become the base of NewCo so I don't blame him from a business perspective,

I think that's a bit cycnical. He was carefully vetting and staggering the releases well before he decided to jump ship for the very reasons mentioned already.

but as the leaks get less and less significant the process of hype, announcement and discussion is going to get really tedious.

I'd argue they are no less significant. Not even the slightest bit. Furthermore, I'd say that any hype that he engages in is desperately needed to even keep these revelations on the radar.

Not sure what country you are in, but the last few rounds of revelations have been focused on the NSA's efforts in a variety of other countries. This necessarily makes a bit less of a splash here, and could be construed as less relevant (though I respectfully disagree there), but I assure you, in those countries where the news broke there was thunderous outrage, and continues to be.

Bottom line for me is that if he read each new announcement in the middle of a three-ring circus, if it wasn't translating to legislative and sentimental change, then he wasn't hyping it enough.

Edit: A less cynical read on Greenwald's motivations for starting a new company can be divined from the article as well, straight from the mouth of the horse:

If you work for MSNBC or for CNN or whatever, you’re basically nothing more than an employee of a large corporation, and in order to thrive in large corporations, the attitude you need is somebody who gives power what it wants rather than looking to subvert it or to be antiauthoritarian. Antiauthoritarians don’t succeed in large corporations. They get expelled by them.