And being that he is such a foodie, (it seems) and Bologna is very popular for that.
LOL!!! Please, stop, RS is NOT a foodie by any definition or, stretch of the imagination. Food and drink are simply fuel, his palate or, level of appreciation for food and it's place in that country's culture is one of his short comings as a tour guide. While he readily admits that his interest in the subject is limited, he attempts to make make up for this by having Fred Plotkin and others to discuss the topic on his show. Unfortunately, Spain, France and Italy are cultures where food is the essence of those respective cultures yet, he simply glosses over the subject. What I would pay to see RS and Anthony Bourdain/David Chang/Colicchio have a sit-down discussion about their travels and the topic of food comes up.... The Scandinavian (RS own ancestry) food scene has exploded in popularity, been the leading edge of food travel renaissance yet, RS is remarkably oblivious to it's happening and significance. I like RS for a lot of things and I'm forever grateful for having his book during my first trip however, food is not one of this strengths.
As for Bologna...go. Yes, fantastic food, fun nightlife, exceptional narrow alleyways crammed with lively and convivial (RS favorite word) diners enjoying life. It's a bummer it's not given it's own section in the Italy book but, consider the other top-tier destinations..where do you put it? These books are geared for the first time visitor, Italy is covered in at least 3-top tier destinations, include their surrounding areas, significant locations and the major cities, all the places to visit, sleep and transportation options, you run out of room fast.
If, as others have hinted or, rumored at, keep the Italy book as it cover the top-tier, must-see locations, then, put-out a pair of North and South books covering the 2nd & 3rd tier destinations where places like Bologna, Ravenna, FVG, Sicily, Sardinia, Alberobello...can be found.