I have a book on my wish list that PBS says will be releasted on 1/31/2012 but on Joan Johnston's web site it says it will not be releasted until some time in 3/00/2012, How does PBS get its dates and what is the real release date?

If the one you are referring to was Texas Bride, according to Amazon the release date is 03/27/2012.  So I am not sure where PBS gets that info, but you can always submit a change to the book data if it is incorrect.  Just click on more options and "Edit Book Data".  Then you can input the correct release date (which seems to be 03/27/2012) and the reason for your change.

The book dates are pulled from a the database that runs the site.  Usually that matches whatever info Amazon.com has. 

As far as the correct pub date, usually author's websites are pretty accurate about those things.  I would also do a search on the publisher's website to see if there is a publication date there.  Since the publisher is the one actually releasing the book, I tend to think they are the most accurate (although sometimes books are released a couple weeks early of the "offical" date).

For what it's worth, I have been told by a member of the Data Corrections team that they do not do any edits before release date.

As Sally has said, the Data Corrections team DOES discourage sending in edits on books before they are actually released, as the information submitted is subject to change (and often does, several times, before the book is actually published).  Rather than have many pre-release submissions sent in, it is preferred that edits be sent in only AFTER the book has been released, and that way the data submitted is not as likely to change nor are as many data submissions needed to make the book details accurate.

 A lot of book clubs get and send books to their members 30-45 days prior to the street date.  I've had a copy of a Robin Carr book via a book club for over a month.  The book was "officially" released yesterday.

It's my understanding that Sally's information is correct    if there has been an official change to the release date, PBS does not pick it up prior to the actual release date.0

Interesting info on the book club editions Mary, didn't know that.  So legit BCE editions can be received and posted to PBS prior to the publisher release date?

Yup, I have a couple of books on my WL that were supposed to be released in 2008 and I'm still waiting! Since the publisher has already registered the ISBN, the change in release date shouldn't really matter though.

Cheryl