At full price, I don't find the Entertainment Book to be enough of a value to purchase. I just don't use enough coupons for it to pay for itself. That said, last year I bought it in April or so, and found that it more than paid for itself with the coupons we ended up using.
So when I saw that the price was $15 (including shipping), I considered it again. But to be sure, I checked the coupons in my area. Honestly, the ones I might use (e.g., Baja Fresh) aren't in there this year, so it's really not worth it this time.
If you're considering buying one, make sure to check the coupons available in your area this year. They do change from year to year, and you may find the changes don't suit your wallet.