I kind of like Byline better. I just brought the premium version of NetNewsWire mobile and I'm also a little disappointed in it not having the ability to read it cached offline version of webpages. That is a feature I've grown to love especially when taking the subway.
All I want from Byline is Instapaper support, twitter support, the ability to like an article and see who else likes it. After using Newsstand, NNW 2.0, and Byline I think that all are good in their own way but none is clearly set apart from the rest. All have nice interfaces but they all need to take full advantages of the abilities of Google Reader.