J Tanner -- thanks for the additional information. I forgot to look at the Kindle format version. He is selling there better than in the paper version I viewed originally, but hardly in any stellar way.
His two highest bestelling categories appear to be lit-fic (which is consistent with the page I read), which isn't a particularly top-selling category generally, and then he's at the bottom of the top 100 of genre romance's "romantic suspense," which is an out-and-out mis-categorization (and it makes me crazy when authors do that; anyone who reads romantic suspense is NOT looking for a story about a guy finding himself through sex, which is what the product description seems to be!).
But, really, I don't think he's any huge hit, and only appeared that way because of some odd trigger in Rhush's past experience with Amazon, possibly aggravated by the book's miscategorization as romantic suspense. Or the author could be buying ads, and I just didn't notice them, b/c I've become pretty blind to advertising online.
This has been interesting, though, and I'm glad Rhush brought it up -- the way certain authors/books can appear to be doing better than they probably are, and you have to do some digging to see the reality, but not everyone will do that digging.