The drumbeat of optimism was heard on the floor of the London Book Fair, and it is echoing in the corridors of New York publishers, as well: Sales, it appears, are improving. The AAP came out with stats that chart a “meager” growth rate in 2001 of 0.1% overall, with trade sales actually dropping 2.6%. But 2002 has started with a nice bump in sales in many categories, according to the latest Bookscan figures. The overall figures show an increase in unit sales of approximately 10% for the first eleven weeks of 2002, compared with the same period in 2001. History continues to show strength, even surpassing the jump in sales that began in the aftermath of September 11. Romance, which was very soft in the fall, has jumped up 14% over last spring’s sales. The cooking and entertaining category has softened since the fall, but is still up over last spring’s numbers by almost 12%, while gardening is down somewhat. Travel is still down, but the post-September freefall is over. The same cannot be said for computer books: the stagnating sales of PCs have taken their toll on manuals, which are down 20%.