I actually sat down and did a count for each category at the Sony store. Here's what I came up with:
Art & Architecture 370
Biography 3,131
Business 4,443
Children 2,278
Computer 845
Cooking 260
Drama 183
Education 1,883
Entertainment 1,123
Family & Relationships 932
Fiction & Literature 13,270
Health, mind & Body 1,760
History 4,340
Home & Garden 194
Horror 809
Law 595
Manga & Graphic Novels 87
Medical 1,502
Music 342
Mystery & Thrillers 5,366
Philosophy 2,176
Poetry 235
Politics & Government 2,266
Psychology 596
Reference 1,842
Religion 2,412
Romance 7,531
Science & Nature 2,815
Science Fiction & Fantasy 3,412
Self Help & Improvement 1,924
Short Stories 2,387
Social Sciences 5,207
Sports & Games 716
Travel 700
Assuming I've typed them all correctly, it should total 77,932.
