In some ways, I'm starting to think the climate change talks about CO2 overshadow a more important threat: the oceans ecosystem.
Just read a report today about how it's collapsing and deteriorating quicker than we previously though. CO2 and ocean acidification is but a part of this, but at 450ppm it becomes a serious serious threat.
And I think the "won't" is too strong for the article. Also, the article mentions how ocean circulation may be the more pressing matter, and the melting of the polar ice caps is changing and messing with that ocean current. That melting can be caused by increased CO2 in the atmosphere, so I don't think this paper rules out rapid change in any way. However, I couldn't read the paper, so I'm just basing this upon the synopsis and the article.