This year's influenza vaccine covers the 2009 pandemic influenza A H1N1 strain, an H3N2 strain, and influenza B.

For the vast majority of people, the benefits outweigh the risks, yet both the benefits and risks are small for the average individual. Any questions, ask you primary care doctor.

http://www.cdc.gov/h1n1flu/

http://www.cdc.gov/h1n1flu/estimates_2009_h1n1.htm

http://www.cdc.gov/h1n1flu/cdcresponse.htm