I have occasionally been offered a title from my WL with a diff ISBN. I almost always accept cause I don't care if I read in PB or HC. I usually add all PB and HC versions when I first put a book on WL, but sometimes I miss one.

However,  I have often posted other versions of WL books that have hundreds of wishers, but only once did anyone accept.  Do most of you not accept the emails offering other versions?

I have those turned off.  I frequently WL audiobooks that are available in print and was getting a ton of emails. 

Whenever I post a book that's WL in every version but mine-I advertise it in the WL thread of the genre it's in, if there is one there.  I put it in my signature and since I post a lot, that usually generates a response unless there's only 1 wisher for the book.  You can also offer it in the book bazaar.  I will also tag the WL versions with "x posted under ISBN xxxx".  

I turned those off a long time ago also.

WAAAAYY too many e-mails for books I wasn't interested in ordering.

Jeez, I guess I am glad that lots of people have those emails turned off 'cos I am sweeping in there and snatching those "similar to your Wish List" books. Actually I don't get all that many of them, maybe once a month if that often, but of course it totally depends on which books (or audio books) you are wishing for. I am always glad to get one of those notices and then hope I am the first to request it!

Remember tho, that there are lots of books that do not have all the various versions linked so in that case the email would not be going out of those who wish to be notified. I wish there was some way to link books without asking the Team to do it for us.