If you message me that my book has been requested by one of your reviewers, and I never hear back from you, what do you think that makes you? Last month Up in Flames, 33 words that takes like a half hour to read, and A Perfect Fit were both requested. According to this one review site. But I never heard back from them. Hummm...interesting.
I've had this sort of thing happen in the past, but never two books with the same site, at the same time. I would think if your book is being requested then the reviewer is ready to read it as soon as they get their hands on it. Wouldn't you?