Let me make this easy. Nothing has changed about the ground rules that should apply. You don't need them to sign a release and you certainly don't need to--and shouldn't ever--show them anything. All you need to do is Journalism 101--quote them accurately and fairly. Of course, some sources may then refuse to be interviewed. So be it.  

When I wrote my first book-- Stalking the Divine-- I told my subjects that they could read what I had written about them prior to publication. This seemed fair to me, even though I don't do this with articles. The book was not an expose' or a work of investigative journalism; it didn't seem as if my subjects would want to change anything that would wreck the book. And since they had generously opened up their personal histories to me, I wanted to make sure I had the details right and that I didn't wind up printing anything that made them miserable.

The publisher sent me standard release forms later on; I was required to get them signed. I think you can tell your subjects that you will probably have to do the same when you line up a publisher.

My second book-- Kabul Beauty School: An American Woman Goes Beyond the Veil-- was co-authored. The other author took care of all this kind of stuff.

I recently published a non-fiction technical book. I never had any interviews. I sent the publisher a detailed book proposal and URLs to numerous writing samples of mine that have been published in numerous places. My book was accepted and I wrote and published the whole thing without ever even seeing in person most of the people I worked with. My book is on the front page of www.relevanttechnologies.com. It is a computer security book. I write mostly on technology and computer security.

I, too, am a 30-year journalist, author and columnist. In general,  you do NOT need to obtain written releases if you are dealing with public officials whom you interviewed as a journalist. They knew you were a journalist, they saw your pad and pencil and recorder, they consented to that interview.  No issues --- unless of course, an agent or publisher makes an issue of it. Some do; some don't. The fuzzy area can come with private individuals....some former drug addict telling you his life story, for example. Again, interviewing him as a journalist, identifying yourself as such will legally cover you.  But in this case, it's a slightly more likely a publisher or agent will ask you to get releases -- not releases for the information but permission to use their name and tell their story. Tip:  tape record everything -- in person or on phone. Save all the emails. In many states (including mine),  you don't have to disclose tape recording on the phone as long as you identify yourseslf as a journalist and it is clear to the person that this is an on-the-record interview being conducted for attribution.    Of course, releases are always a good idea. But not always necessary. And the problem is, you often will not KNOW if a release is critical and you've already finished your work and submitted a manuscript. Then the interview subject may be gone (or dead). There are few better books on writing nonfiction that the ones written by Elizabeth Lyon, a regular at the Writers Retreat Workshops. Look up on Amazon books.  She even accepts personal emails. Again, there is a distinction between what the publishing world will require (Elizabeth's expertise) and applicable state laws or court rulings.  It is my opinion, however, that a working journalist who always identifies himself as such, has ample protection in this area.  
-- david chartrand, kansas city    dvc@aol.com

PS -- On interveiw subjects wanting to see/review your copy, I'm more philosophical about that. I'd never do it for routine news/column/reporting work.  But a book is different. too much at stake. More than my personal pride is on the line; the agent and publisher have their necks stuck out there as well. It's not worth taking a chance on errors.  So I often take SELECTED chapters in draft form and submit them to the folks who are quoted or mentioned in that chapter.  Lots of authors do this, for protection.  I don't offer them editing or veto authority; I only offer them the sneak peek.  I tell them in advance that I may or may not accept their requested changes. Even if they HATE it, I may not change a thing.  Most are fine with it and appreciate the gesture.  In many cases, they find little errors in the text -- or offer new detail -- for which I am grateful. Hope that helps.

A couple of years ago, a writer and I produced a book on rural health care. We prepared a simple release form. Everyone we interviewed or photographed signed a release. We were not doing any investigative reporting, but we were making sure we protected ourselves and the publisher, and that the subjects understood what we were doing. Very little material in the book dealt with potentially harmful content. We were concerned about covering a rural clinic in Iowa that cared for domestic and sexual assault victims. No one refused to sign. All were pleased we were dealing with the health care issues AND the more difficult lack of resources in rural areas.
Jokingly, we always asked who they wanted to play their part when the movie was made. It always brought laughs and warmed the relationships! A little humor goes a long way.

When you do place your book, your publisher may still ask you to get written permission for the interviews - we do.

A permission form will likely include the text you plan to publish within it so that the person granting permission will be able to review and approve your usage.