So you'd be more likely to believe them if they were verbose? Most of them are fairly direct denials. That's not to say that they're necessarily true, but they don't seem like especially weasely statements.
Given the actual denials, I will assume that, at a minimum, everything about the story that they didn't deny -- that is, the scope of the customer data which has been provided by those providers to the NSA -- is implicitly confirmed, and that the (mostly irrelevant) details they have denied are in doubt.
We need press that is capable of communicating the grey areas as you did in your top comment here, ideally in a way the masses can grok.