Besides the very good overview of the Hadoop ecosystem, the GigaOm article gets the whole open source thing wrongly:
The only potential obstacle for these and aspiring Hadoop vendors appears to be Hadoop’s open source roots. […] This is a task made only more difficult by the fact that Hadoop creator Yahoo keeps releasing new open source tools and distributions (like it did this week with Hadoop with Security and Oozie) already proven to work at web scale.
To make it clear: it’s great that Yahoo! created Hadoop and open sourced it, but everything should’ve stopped there so other companies could start building on the community contributions and make money out of it. Fantastic idea GigaOm!