As we approach the end of what has been another roller-coaster year for our country, it seems an appropriate time for an “annual checkup” on healthcare reform in the U.S.

Like many of my colleagues, I have followed the implementation of the monumental Patient Protection and Affordable Care Act (ACA) with great interest, mild trepidation, and a small measure of optimism.

It’s hard to believe that almost two years have flown by since the passage of this historic, game-changing legislation that will influence how healthcare is delivered and reimbursed in the U.S. for decades to come.

Although debates will continue to rage about the law and its sweeping array of mandates, the ACA and the overwhelming majority of its provisions are likely here to stay.

The popular media tends to focus on the “chief complaints” — a few hot-button issues such as “death panels” and the significant number of state-sponsored challenges to the legality and “constitutionality” of some of the law’s provisions.

However, in the course of a comprehensive “annual physical” exam, it is clear that a surprisingly large number of the law’s provisions have already gone into effect — smoothly and as planned across the entire industry.

Here are just a few …

In the first year (2010), insurers complied with a variety of new requirements, including increased mandatory reporting of administrative data, continued coverage of children under their parents’ policies until the 26th birthday, strict limits on reasons for discontinuing coverage, and free preventive screening services for adults.

Nonprofit insurers faced a new requirement that they maintain a loss ratio of 85% or higher in the large group market and 80% or higher in the small markets in order to take advantage of Internal Revenue Service tax benefits.

Other provisions that went into effect in 2010 included new tax credits available to small businesses (25 or fewer employees) to help with employee premium costs and the expansion of Medicare to small, rural hospitals and facilities.

In January of this year, Medicare beneficiaries began to receive free preventive care as well as a 50% discount on the cost of covered brand-name prescription drugs to tighten the Medicare Part D coverage gap (doughnut hole), and grants became available to states to develop programs aimed at delaying the onset and reducing the prevalence of chronic conditions in their Medicaid populations.

Hospitals also began to feel the impact of ACA this year when the federal government stopped paying states for Medicaid services related to certain hospital-acquired infections – a prelude to the planned reduction in Medicare payments for preventable hospital admissions scheduled to take effect in 2012.

Some of the states that have mounted legal challenges over certain aspects of the law have begun to take action on others; for instance, Pennsylvania’s Republican governor recently got the ball rolling on the insurance exchange component.

On the policy front, the Centers for Medicare and Medicaid Services met its deadline for developing the CMS Center for Medicare and Medicaid Innovation, the body that will oversee testing of innovative payment and delivery models such as bundled payments for care improvement models, the comprehensive primary care initiative, and Partnerships for Patients.

Although all of this suggests that the general health of healthcare reform is in pretty good shape, the coming year brings a lot of uncertainty.

The U.S. Supreme Court is set to decide on a course of treatment for at least one nagging problem — the individual mandate – that may include surgical excision.

The 2012 elections could result in power shifts that may affect the law’s “mortality” (i.e., efforts to repeal the entire law) or, at the very least, its “morbidity” (i.e., efforts to limit funding for the implementation of certain provisions).

On Dec. 2, Donald Berwick, MD, left the helm of the Centers for Medicare and Medicaid (CMS) and many in the health reform movement mourned the loss of a leader often described as a visionary.

Dr. Berwick has been open about his failures and frustrations as well as his successes in trying to engineer a rapid transformation of the healthcare system while warding off political attacks from various quarters.

What can we expect from his likely successor, Marilyn Tavenner?

Ms. Tavenner has risen through the ranks from nurse to CEO to a regional executive for HCA and the second in command at CMS.

Writing for HealthLeaders Media, John Commins suggests that she might be the “anti-Berwick” – a more “practical-minded,” “consensus-building” leader. But that remains to be seen.

Tune in next year for another update.

David B. Nash is Founding Dean of the Jefferson School of Population Health at Thomas Jefferson University and blogs at Nash on Health Policy.

Originally published in MedPage Today. Visit MedPageToday.com for more health policy news.