Today "The River, By Moonlight" got its third review of this current virtual book tour.  It was a good one, which made me happy; but, chastened by the responses to my last blog on the subject, I hesitated to thank the site host, and instead emailed Mary Lewis, who is running the tour  ( http://blogstopbooktours.wordpress.com/ ) to ask her opinion of the matter.  This is Mary's reply:

"Many of the authors who have toured previously with Blog Stop have stopped by and thanked the reviewers.  I think it's a great thing to do.  If you're inclined to say thank you, then please do." 

I returned to the site immediately and posted my thanks.