Each game is run by one person, and is made up of a number of identical rounds (usually 5)Over at the LJ community dedicated to this, which rejoices in the name of
Each round, the person who's running the game picks a book, and tells everyone else the author, title and some description of the book (I usually use the blurb on the back and an extract from the text). A fixed amount of time passes, during which the players write and submit a plausible first line. Then all the first lines, together with the real one, are published and the players have to guess which is the real one. A point for guessing correctly, a point for someone guessing yours. At the end of the game, the player with most points wins.
the_book_game, I am moderating the next round. Feel free to come and join in.