Apple is a steward but puts a lot of thought and care into how its brand is presented on its own pages, let alone on those of a third party.

In a best case scenario they'd push back the launch of the site to make sure that everything is up to their standards (which logos they appear next to, amongst, etc; what their blurb says), but their second choice is to forbid anything about them on the site whilst they think about how they want it to look.

Apple is a steward, but they chose not to have their logo in the footer. You can see them on the list of the stewards http://webplatform.org/stewards/

That's exactly my first thought. Apart from the TNW article Apple is mentioned only in this blogpost http://blog.webplatform.org/2012/10/one-small-step/

Alongside Google, Microsoft, HP, and Nokia's logos? I wonder ...

maybe they can't use logo yet http://i.imgur.com/VdYXj.png