Open Source: when it makes sense (And: how Apple behaves)

My current company's tagline is: "Realize the benefits of Open Source". In practice that means: Of each application that we assemble for our clients, all or most of it's components are built with open source technology. However much makes technical, economical and business sense.
And it often does make good sense.
An ARS Technica post argues that Apple 'gets it' in the way they choose how to use Open Source licensing and for what (not).
This in response to a post on O'reilly's Mac Devcenter that argues that Apple is not a good Open Source community citizen.