The study by marketing consultancy Five by Five found that 74 per cent of brand marketers saw social media as the top priority for launches.
Sales promotion ranked second and email marketing third, while TV advertising ranked sixth, falling behind press advertising (fourth) and PR activity (fifth), Five by Five's research said.
According to the consultancy, social may now be the advertising medium of choice because marketers are facing faster product launch timeframes.
Indeed, 81 per cent of the 730 respondents said that during the last five years, the average time between an idea originating and the product launching had shrunk.
Well over two thirds said they typically have less than six months to prepare for a product launch.
Commenting on the growth of social advertising, Five by Five creative director Martin Flavin said: "Social media has become the most important way to generate buzz for new products and services before they appear. Shareable content and social engagement allow brands to create a groundswell of pre-launch interest in a way no other channel can match."
This view contrasts with that of WPP boss Sir Martin Sorrell. Speaking at a Hill+Knowlton Strategies conference during September, Sorrell said search was more powerful than social, highlighting that the agency spends more on Google than it does on Facebook, for instance. Sorrell did concede, though, that social was useful at building brands over the long term.
Elsewhere in the report, 80 per cent of those surveyed argued that launch marketing was "completely different" to other forms of marketing and required specialist handling.
"For many senior marketers, launches have become more multi-faceted. This means that effective communication internally, alignment with external agencies and the correct investment of time and budgets is crucially for ensuring a successful launch," said Five by Five strategy director Michelle Mitchell.