The surprise announcement this past week that the White House is delaying a requirement that many employers offer coverage raised questions about other major parts of the biggest expansion of society's safety net since Medicare nearly 50 years ago.
One delay may not matter much in the end. People will judge Obama's law on three main points: premiums, choice and the overall consumer experience.
Only partial answers can be gleaned now, and they don't necessarily fall along predictable lines.
Basic economics suggests premiums will be higher than what many people who buy their own coverage pay now, especially the young and healthy. The new policies provide better benefits, and starting next year, insurers won't be able to turn away the sick. But the pocketbook impact will be eased by new tax credits and other features that people soon will discover.
As for choice, Obama's plan isn't likely to deliver the dozens of options available to seniors through Medicare. But limited choices may not be seen as a step backward because in most states the individual health insurance market is now dominated by a single insurer.
The consumer experience shopping online for insurance remains the biggest unknown and a risk.
Squads of technology experts federal, state, insurer and contractor employees are trying mesh government and private computer systems together in ways that haven't been tried before. It may not feel like Amazon.com. Many people could default to enrolling the low-tech way, through call centers or even through the mail.
Health care politics divided the nation even before the passage of the Affordable Care Act in 2010, and the law's full implementation four years later is shaping up as a tale of two Americas.
The rollout might go well in mostly Democratic states that prepared, while it clatters and clunks in mainly Republican ones that resisted Obama's law. Millions of poor people will be denied coverage next year because they live in states that are refusing the law's Medicaid expansion. But most workers now covered on the job should not see major changes.
With political strategists already honing health care attack lines for next year's congressional elections, a former U.S. health secretary has an admonition for both parties. Mike Leavitt put in place the Medicare prescription drug plan for President George W. Bush in 2006 and now heads a consulting firm that advises states on Obama's law.
"It's important for all of us to remember that it's not political parties who are affected in the long run, it's people," Leavitt said recently. "It will be millions of people ... many of whom are the less fortunate, and those who have dramatic health problems."
A closer look at the three big questions:
The Obama administration sees encouraging signs in states that have released premiums for next year, as well as from rates filed directly with the federal government but not yet publicly revealed.
"We are seeing increased choice and affordable premiums," said Mike Hash, head of the Department of Health and Human Services' health reform office.
But what will consumers see?
The data-crunching company Avalere Health found that in nine states that have released premiums, the rates appear to be lower than the Congressional Budget Office estimated when the law was being drafted in 2009.
But Avalere vice president Caroline Pearson acknowledges that doesn't represent the cost comparison a consumer might make. Most people who now buy policies individually could see an increase from what they're now paying.
"The benefit design is going to be richer than what is typically purchased and available today ... and the rules require insurers to sell a policy to whoever wants it, regardless of health status," she said.
That still doesn't get you to the bottom line because most consumers will be eligible for income-based tax credits to help pay premiums. The plan they pick also could make a big difference.
Jeremy Gilchrist, a self-employed meteorologist from Winooski, Vt., has been uninsured about four years. In his mid-30s, he's in good health, and he says he can't afford premiums on a skimpy budget.
"For most people, it's going to be a financial decision," Gilchrist said.
According to the online Kaiser Family Foundation's health reform subsidy calculator, Gilchrist would be eligible for a tax credit of nearly $2000 on a standard "silver" policy that costs $3,000, leaving him with $1,000 to pay.
But he can also take that $2,000 tax credit and use it to buy a cheaper policy called a "bronze" plan, leaving him with only about $500 to pay annually. The bronze plan meets the new requirement that virtually all people in the United States have health insurance. But if you get seriously sick or injured you'll wind up paying more out of your own pocket.
Still, the premium would come to $42 a month for Gilchrist. "The bronze plan would be lower than my car insurance," he said.
If Gilchrist were a smoker, which he is not, the law would allow insurers to tack on a penalty of up to 50 percent of the premium.
With time, the decisions of millions of individual consumers will reveal a true bottom line.
The typical Medicare recipient has about 30 private insurance plans from which to choose. There may not be nearly as much choice for families and individuals under the health care law. How much that will matter remains to be seen.
It's partly because in most states a single insurance company currently controls more than half the market for individual coverage.
The administration says that's going to change for the better. In three-quarters of the markets the federal government will run, there will be at least one new insurer.
But areas of concern are emerging. New Hampshire could end up with just one insurance company offering plans through the new marketplace. In 36 of Mississippi's 82 counties, no insurer has yet signed up to offer coverage. Bigger states, however, don't seem to be having problems attracting insurers.
"The individual market for 2014 will look a lot like the individual market today one or a handful of carriers dominant in most states," said Larry Levitt, a leading expert with the nonpartisan Kaiser Family Foundation.
But people will be able to move more easily from insurer to insurer, he added, which should bring more competitive pressure.
For people without job-based coverage, shopping for insurance under the new system is supposed to be as smooth as using a major online site such as Travelocity or Expedia.
But in a recent report, the Government Accountability Office raised concerns about the sheer technological complexity of the task and the short time left to accomplish it.
The goal is for consumers to be able to find out the amount of the tax credit they're entitled to and sign up for a plan in real time or close to it. For that to happen, the computer systems of several major federal agencies, the states and dozens of insurance companies have to be able to talk each other, and the information exchanged must be accurate.
Testing the connections is underway. "We really feel very much on target for Oct. 1 and ready for open enrollment," said Chiquita Brooks-LaSure, a top HHS official overseeing the rollout. "We are meeting critical implementation deadlines."
"My guess is some of these states are not going to be up and running on time," said Dan Maynard, president of Connecture, a health technology company building three marketplaces.
That wouldn't necessarily mean some consumers will have to wait. People could sign up through call centers.
"You could have a very light online (marketplace) and have a lot of things drop to the call center and claim success," said Maynard.