We analyze data on the intention of U.S. adults to receive novel H1N1 vaccine if available this fall, and studies the relationship between the intention to be vaccinated against novel H1N1 and the uptake of seasonal influenza vaccine last year. We surveyed a nationally representative sample of U.S. adults (n=2067) via the Internet between May 26th and June 8th, 2009. Our results imply a vaccination rate for novel H1N1 of 49.6%, which corresponds to roughly 115 million adult vaccinations. Moreover, novel H1N1 vaccination intentions are strongly associated with seasonal influenza vaccinations, suggesting common attitudinal barriers to both vaccines.