It's generally unsafe to assume that quotations indicate a high degree of correlation between the person being interviewed's intent and the text within. Very often reporters start with a point they're trying to make and then search for snippets to support that, freely editing to further that end.
It's also a reason that if you're being interviewed for publication that it's a good idea to ask for the right to review it before publication to make sure that you're not being misrepresented – at least not in any way that offends you.
Although I've never gone to journalism school, I have the impression that journalists' professional ethics forbid this, because it deprives them not only of the ability to misrepresent you but also of the ability to harshly criticize you. Clearly, for instance, the famous Wired hit piece on Ted Nelson never would have seen print if it had needed Ted's signoff. In the case of this story, when talking about ViaWeb, they mentioned the Morris worm (which pg never does voluntarily, as far as I can tell, even though it's by far Morris's most famous achievement) but they got the story wrong (or anyway this is the first time I'd ever heard the release was accidental, as opposed to the virulence.)
I guess the short version is that they value independence from sources more highly than accuracy.
In most any article of any significance I have been a part of, I get a call a couple weeks after the interview by a fact-checker that double-checks the spelling of my name, and generally asks me "would you say the following statements are true: ..."
so there's some level of accuracy checking, you just can't do it with the whole story otherwise you'd be having the subject writing the article to their exact liking, and that wouldn't be journalism anymore, it would be PR and promotion.
Remember - who is in the best position to shape perceptions of the press? :) Most popular journalism has the same relation to truth as screenplays. Professional ethics has never really been a barrier to massaging the story.
A few journalists have even told me that when they really want to needle someone they will quote absolutely verbatim, down to every "um", "ah" and mistake but carefully out of context so as to make the subject come off like a raving idiot.
It's different in an investigative story vs. an interview. If they're just cherry-picking quotes for a story, you probably won't get to review it. If they're trimming down an interview, then I don't see a real conflict since it's being presented as something representative of what you said.
It's also a reason that if you're being interviewed for publication that it's a good idea to ask for the right to review it before publication to make sure that you're not being misrepresented – at least not in any way that offends you.