For the second time in recent weeks, I have found reviews that have no star ratings--- am I to assume that means they gave the book zero stars?  The reviews themselves do not seem to reflect a "zero" rating so I figured they just didn't give a rating, though I thought you HAD TO give a star rating in order to post a review or get the book onto your BIR list.

(see reveiew for " Hitler's Niece")

The two that I saw there were both from 2008. 

There was a time that you could put books on your BIR and write reviews without giving a star rating.  As I recall, the stars were just something you did separately.   Based on the reviews on that book, that change happened sometime in 2008.  The February 2009 review has stars.

I was thinking the same thing as Ruth--when I've looked at different reviews, it seems like all of the reviews without stars are older reviews, so I just assumed that they linked the stars and reviews sometime after implementing the review feature.

You can actually also rate it in order to write a review, and then clear your rating and have your review remain. At least, you could as of a while back when I last heard of it, and the function to clear your rating is still there,  so I assume any review you wrote still remains if you do so just as it did then.

huh, I didn't know you could "clear" a star rating, I thought you could just change the number up or down.

I used to do this often!  When more info about a book (not yet in print) is available on an author's website or another site like Amazon.com or FantasticFiction.com, I'd copy the info into a review using a 5-star rating, give proper credit to where it came from, then remove my rating.  For books in a series, this can be valuable and timesaving info for fans.  However, I've not done this in a long time.  I used to be very active on the site but have not been the past few years.

For example, this book Bitterblue by Kristin Cashore was a long-awaited sequel, and it was cancelled by the original publisher.  I wrote a review "EDIT: 10/15/11: This is the correct ISBN: 9780803734739" and then cancelled my rating.  There are still 11 wishers for this book which is even called "CANCELLED" when you are on that page.  But this is the actual Bitterblue that came out (and was fantastic!) 

Another example is for Shadowhunters and Downworlders A Mortal Instruments Reader.  I'm a huge fan of the series and found info about this "fan extra" through Amazon.  I gave it 5 stars, wrote this review and then cancelled my rating since I'd not actually read the book. 

from Amazon.com:
Publication Date: January 29, 2013
Cassandra Clare’s Mortal Instruments series, epic urban fantasy set in a richly imagined world of shadowhunters, vampires, werewolves, fairies, and more, has captured the imaginations and loyalty of hundreds of thousands of YA readers. Originally a trilogy (City of Bones, City of Ashes, City of Glass), the series has extended to six titles, plus a prequel trilogy, the Infernal Devices, and a planned sequel series, the Dark Artifices. A feature film is planned for 2013.
Shadowhunters and Downworlders, edited by Clare (who provides an introduction to the book and to each piece), is a collection of YA authors writing about the series and its world.

These reviews still show up in my review list, which I'm glad to see.  I do go back remove useless info when necessary, and these reviews are deleted from my list.