From my perspective, it's a lot like the dilema faced by Scotts (the stamp catalog people) once countries started issuing gazillions of stamps. The books went specialized. There's a US Specialty, a British Commenwealth, & Other Countries. Many collectors collect obsolete rack chips, others collect LE's, and others collect roulettes. Some collect (or sell) two or three of the categories. But, many collectors just collect one category (or even a small portion of one category) and can't afford the price of an all-inclusive book. $48 was a lot for me to pay when I only collect Meadows (if there is one), Apache (if I could afford one), SS Rex, Eldorado Club, and Horseshoe (but NO LE's). I'm thinking of adding The Mint and Boulder Club, since they were on the same block as the Apache Hotel, but an $80 or $100 book would be hard to justify for just a handful of obsolete casinos.
I'm also thinking that the new LE collectors that Gene talked about just entering the hobby might hesitate to buy an $80 or $100 massive catalog, but might pop $40 for just an LE catalog. Dealers, of course, and general collectors, would likely pop for all three. I think the market could bear $30 or $35 for a specialty version, and sell more overall because you weren't required to buy all three.
I confess that since I collect very little Nevada, if the price for the catalog of rack chips were over $50 I'd probably borrow a copy and Xerox the few pages I need. Frankly, I think the hobby is now big enough so there are really four hobbies - Nevada rack chips, LE's, Roulettes, and the rest-of-the-world not covered in TCR.