Book Expo America is upon the epically embattled publishing industry once again. Things really heat up today and tomorrow-this is at the Javits Center, over at the ass end of Manhattan-with author signings and discussions like "Book Reviews 2010: What Will They Look Like." But the most attended event at the slower Thursday session was a panel of four publishing CEOs. It was moderated by former New Yorker editor, founder and editor of The Daily Beast, and ACTUAL BOOK AUTHOR Tina Brown. Elegant in pink, Brown's role was Emissary of New Media-"I now run an Internet site," she said helpfully-to the lovable but philistine Print Masses.