In today's keynote at OSBC RedHat's CEO Jim Whitehurst claimed that even companies like Google, Amazon and other cloud players are always collaborating .. not directly but in the form of collaboration via the various open source projects they build their offerings on.
While that's true to some extent, the reality IMO is that many of these companies end up with forks of key projects such as MySQL or Xen or use extension points to write their own core bits that are not open source and never will be. If you talk to ex-MySQL people they will tell you that while there was a lot of testing and other "low end" contributions by the community, almost no major contributions for MySQL came from random outside users. That is the general sentiment I've heard from most open source organizations, communities and projects and certainly our experience in WSO2 as well. Even in Apache, its usually people who are fairly committed to the project (either by employment, which is most common, or by personal interest/choice) who contribute meaningfully; its very rarely that you get a sizable contribution from an outsider.
In fact, the (ab)use of open source by online services companies like Google etc. is exactly why the AGPL license was created. For the uninitiated, AGPL is a viral license like GPL except that even online hosting is considered "distribution", thereby forcing service providers to ship the source code for any modifications they've done. Personally I'm not a fan of such aggressive tactics to get people to contribute (that's why ALL WSO2 software is Apache licensed) but there are many people who come from the free software mindset, in comparison to the open source mindset, of the FOSS community who are not happy with the Googles of the world not having to share any code at all even though they get a lot out of FOSS.
So IMO Jim's wrong on this- Google and Amazon and other major closed cloud platform players will NOT share anything they absolutely don't have to. As a side-effect, they will not touch any AGPL code because it will force them to be a commodity and that results in loss of key competitive advantages for them.
The FOSS movement is about giving power to the people. Cloud is a major risk for that as the cloud vendors are incentivized NOT to have a common denominator. That's why there's no freedom in the cloud without using a truly open source PaaS and building your own thing on top of it.