Genius. Makes you wonder why someone else didn't think of this sooner? If Google gets on board with this endeavour, it'll be a force to be reckoned with. As one commenter on the story points out, why isn't Wordpress on the top of the list? It powers a large chunk of the web and arguably is always being hacked and exploited.
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is sponsored by Microsoft and Facebook. It will be jointly controlled by researchers from those companies along with their counterparts at Google,
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That isn't the same. You pay people to break your site for you, this bounty program is paying people to find vulnerbilities in commonly used web software like Apache and whatnot. Two completely different things in my opinion.
There is a better service than the one you posted from Australia called Bugcrowd: http://bugcrowd.com - a much better executed implementation of the idea, but still not offering money to people.
http://hyperboleandahalf.blogspot.ca/2010/06/this-is-why-ill...