Healthcare.gov is a new federal website that brings together information from many separate websites (medicare.gov, healthfinder.gov, and hospital compare). This website provides information about your insurance options, based on your age, family situation, and which state you live in. The insurance information includes both the Medicare plans and the private insurance plans available in your state. Another part of the website is devoted to preventative care - i.e. how to stay healthy. In addition, another section of the website allows you to compare the quality of care in different hospitals. There is a section specifically for Seniors, with information about the new Affordable Care Act and about how Medicare recipients can receive rebate checks when they reach the drug coverage gap (the "donut hole").
Here is a video from the website describing the Affordable Care Act and Medicare Benefits: