Days after the HarperCollins-Hearst deal was announced, the New York Times and Reuters reported that Time Warner Inc., the owner of Warner Books and Little, Brown and Co., and Viacom Inc., the parent of Simon & Schuster, were discussing a joint venture involving their publishing operations. Talk of a possible deal comes a year after Viacom broke off and sold Simon & Schuster's educational-publishing units and suggests that the media giant is looking for greater cost efficiency in its remaining consumer-publishing imprints by sharing operational expenses with Time Warner. Again, though, word of the discussions has unsettled those who fear being the odd man out if a reorganization takes place.