The White House says that once tax credits are factored in, about 6 in 10 individuals will be able to find insurance for less than $100 a month.
"In some states, insurance markets were already regulated to not allow insurers to discriminate against the sick. In those states, premiums will fall, like in New York, where premiums will fall by as much as 50 percent," said MIT economist Jonathan Gruber, who helped design the law. "In other states insurers were freely allowed to discriminate against the sick. In those states, by ending the discrimination, we're going to raise premiums in states like Wisconsin, or some of the Southern states."
Overall, Gruber said, rates are going up for the young and healthy, and down for older people and people who are sick.
When you do choose a plan, you should be aware of what doctor choices you have under your coverage.
To reduce premiums and other costs, many insurers have chosen to limit the selection of doctors in certain exchange plans. Large academic medical centers, which are often more expensive, are excluded from such plans.
"The sticker price will be lower if the number of options are lower," Joe Mondy, a spokesman with Cigna, which is participating in five state exchanges, told CNNMoney. "The issue is how many options can you do without?"
5. The shutdown came and went -- without changing much
The government shutdown had no effect on users trying to sign up for the exchange because money designated for the launch was approved in a previous session of Congress and didn't have to be approved again.
Yet it was partly because of the Affordable Care Act that the shutdown continued so long in the first place.
Republicans attacked the law on several fronts, demanding first that the government defund Obamacare, and then that it be delayed for a year. But when the government reopened, the GOP came away with just a small concession related to Obamacare: two additional reports from the Department of Health and Human Services.
Republicans had wanted tighter income verification procedures for health insurance applicants. What they'll get is a report detailing the income checks the insurance exchanges will use, and a second report that reviews how effective the verification procedures are.
The Republican party is still calling for an investigation into the HealthCare.gov website's problems.