Tax credits will be offered to help families within 400 percent of the poverty level afford insurance.

“This is an historic time for those Americans who never had health insurance, who had to go without insurance after losing a job or becoming sick, or who had been turned down because of a pre-existing condition,” HHS Secretary Kathleen Sebelius wrote in a blog post about the website. “Because of these new marketplaces established under the Affordable Care Act, millions of Americans will have new access to affordable health insurance coverage.”

Some 30 million Americans are currently uninsured.

The exchanges set up under health reform are intended to give families and small-business owners “accurate information to make apples-to-apples comparisons of private insurance plans and, get financial help to make coverage more affordable if they're eligible.”

Healthcare.gov will also give consumers access to their own state exchanges, if they have one. They can also sign up for email and text message alerts.

The website will be part of HHS's efforts in the coming year to market the new exchanges as the deadline looms. It won't necessarily be an easy effort—the exchanges have gotten pushback from some Republican governors, some who refuse to set up a state exchange. Others have complained there hasn't been enough guidance from the government on how to do so. For those that don't intend to set up an exchange, the government will set up one for them.

So far, 20 states are approved to operate their marketplaces, with 18 running state-based exchanges and two planning to partner with the federal government, according to HHS.

There's also the huge hurdle of uninformed consumers who are unaware of what the exchanges do and what health reform means for them. But that's one thing government officials hope the updated website will remedy.

Sebelius promises “the Marketplace will offer much more than any health insurance website you've used before. Insurers will compete for your business on a level playing field, with no hidden costs or misleading fine print.”