The title of the article is pretty sensationalist but it's interesting nonetheless.
Link to the actual study:
http://arxiv.org/PS_cache/arxiv/pdf/...107.5728v2.pdf
In the methodology they exclude privately-held companies, so you have to keep that in mind.
The 147 companies control about 40% of the global corporate wealth (737 control 80% of it).
It looks like mostly banks and investment groups, which is not that surprising. I don't think this will come as a shock to most people.
There
could be some valuable takeaways from this study, but unfortunately I'd bet that it will just be used as kneejerk cannon fodder for people who want to protest without thinking through an actual solution.