It's worth noting that Digitimes is a notoriously unreliable source, one that has been wrong many times in the past about the Amazon smartphone in particular.
I think your extension could provide value if people could choose a field of interest. Like if I could stumble through articles about China or about animals or even about broad things like people or places, that would be neat.
There's nothing in the CC-ShareAlike license about only being able to use the content for non-commercial purposes. I think that as long as you released the Kindle book with the CC-ShareAlike license, you could still charge for it and it would be legal.
Is there any way to turn a timestamp off for a page? Also, is there/will there be an RSS feed for each blog? And I know it's early, but will you be adding domain name support?