Health care overhaul hinges on unfinished exchanges

Much of the uncertainty surrounding the impact of President Obama’s health care overhaul is wrapped up in insurance exchanges, a new concept that will create online health plan marketplaces.

States must either set up their own exchanges — organizations set up to provide health plans to individuals and small businesses — or default to exchanges created by the federal government. People can compare insurance plans — there will be different plans for various income levels — and enroll through a specially created website for each state. They can also enroll over the phone or in person.