Mustapha from ZDNet France was kind enough to answer answer my plea for a Newsvine invite, and now I’ve found time to gather my thoughts.
Newsvine gets many things right. I just don’t know if that’s enough.

The Newsvine team built a content management system for the new media world, which is smart. Useful, human-readable (and guessable!) URLs are built into the system. Revenue incentives for participation are built into the system from the start, rather than bolted on later. (That will save aggravation down the road, certainly.) Content from all sources is treated natively. Simplicity in the design is consistent. I liked what I saw.

Read I am dismayed that the recent Nature article on how web users make snap decisions (50 milliseconds) is already behind a paywall. But I’ll link to it anyway in this context because with Newsvine, the entire introductory experience felt really good until I got to the home page, the front door of my news experience. Then Newsvine felt much the same as other news sites, visually. That’s probably a good thing in some regards (we’re all perviously trained to some degree) but the importance, and distinctiveness, of the “Vine” (reader-contributed material) is not made apparent.

Seed is the term Newsvine uses for sharing/submitting a link for others to follow. Since this contribution has a much lower bar than Write (see below), I expect the greatest value to the “Vine” to come from its Seeds. Of course, this is the area with the most competition, too. I watch the Digg phenomenon and don’t know whether the world has definitely changed, or whether another geek trend is running rampant among the digital early adopters without crossing over. (NOTE: Those who recognize which trends will cross over, and when, are very, very successful. I don’t claim to be one of them, though I’m paying close attention all the same.)

Write Is it the goal to get everyone who would otherwise start a blog, or join a blog network, to make Newsvine their oar in the water? Everybody’s a participant is the banner of the new wave, after all. Catch some of the next wave of participants without worrying about the reaction of the early adopters? (But then how do you reach a new audience?)
I admire putting everyone on an equal footing, and letting the best writers get the value, but with so many places to share opinions and more, I guess I wouldn’t bet on Newsvine being the platform of choice for that level of contribution. The really strong writers can get the same level of return elsewhere, I expect.
Specifics
A few tidbits…
I’m in this same competitive arena, broadly, so I hope my biases are (a) clear and (b) not overly coloring my evaluation. I want new ideas to succeed. I’ve been working on online publications since 1993, and I think the medium still has a long way to go in addressing the human needs in the most satisfactory way. That challenge is one which I take personally, not just professionally. (Although the lack of design of my blog may give the opposite impression!)
I believe news organizations will benefit from the Newsvine lessons, and maybe even envy the content management system, but Newsvine looks like a solution in search of an audience at this point.
Please let me know if you’d like an invite. I won’t hand them out indiscriminately (read here for why), but if you’re reading this, you’re hardly a random stranger. 😉