( CNN ) -- There 's a lot that will happen in 2013 with respect to health care , but the truth of the matter is that most of it will be in preparation for 2014 . That 's the year the Affordable Care Act really kicks into effect . Here are my guesses for what to watch in 2013 : . 1 . The Medicaid expansion . Much of this year 's election was fought over whether Medicaid should be cut . Now the big decision is how much Medicaid will be expanded . About half of the uninsured who hope for coverage under the Affordable Care Act will do so under Medicaid , an estimated 16 million to 17 million people . But June 's Supreme Court ruling made the expansion optional , and states get to decide if they will participate . At last count , 17 states have said yes , and nine have said no . The rest will need to commit in 2013 . My guess is that most will . The Obama administration has decided to play hardball , and leaving that money on the table will be met with screams by the uninsured and providers alike . 2 . Medicaid provider payments . These are going up . Way up . Part of the Affordable Care Act makes Medicaid payments to physicians look more like Medicare payments . There is such a difference that many physicians will see fees for primary care services go up by 73 % . Physicians will be thrilled . Those who think Medicaid costs too much already will not . 3 . The health insurance exchanges . In 2014 , the other half of the uninsured will need to go to the health insurance exchanges to get their insurance . These are tightly regulated marketplaces where individuals will be able to get community-rated insurance and ca n't be turned down even if they have chronic conditions . People who make between 133 % and 400 % of the federal poverty line will get subsidies in the form of tax credits to help defer the cost . But many states are choosing not to form local exchanges , leaving it to the federal government . For those states that opt for exchanges , there 's a ton of work to do next year to get them ready to go . The federal government will be responsible for all the states that are opting out , and it has even more work to do . Expect a lot of news on their development . October 1 , 2013 , is the date they 're all supposed to go live . 4 . Medicare taxes . Taxes are going up . Right now , employees pay a tax of 1.45 % for Medicare ( employers pay an equal amount ) . Starting next year , for couples making more than $ 250,000 that tax will go up by 0.9 % on income above the threshold . Additionally , investment income will also be taxed at 3.8 % for people above the threshold . This is the first time that unearned income will be subject to a Medicare tax . 5 . Medicare reform . This got a lot of attention in the election , and in the first few rounds of fiscal cliff negotiations . Talk of raising the eligibility age is dead for now , and discussions of turning Medicare into a voucher program are in the dustbin of history as well . I do n't think that any huge changes will happen on this front , short of those already put in place by the Affordable Care Act and quietly re-embraced by Republicans post-election . The Obama administration has proposed some new cuts , but almost none of those will affect 2013 . 6 . Insurance transparency . A small but important benefit of the Affordable Care Act will start in 2013 . From now on , insurance companies are mandated to describe all plans in easy-to-understand English in a standardized format . Here 's a sample ( PDF ) . This will make things easier for many people , although insurance policies will still be hard to understand . 7 . Health care spending . Although many believe that health care costs will rise more slowly in 2013 , at about 3.8 % , we will still be spending $ 2.9 trillion . That 's a lot of money . As we continue to fight over the budget deficit and the debt , expect the costs of health care to continue getting a lot of attention . That should account for most of the excitement next year . Whether I 'm right or wrong , we 'll be covering it here on CNN.com . The opinions expressed in this commentary are solely those of Aaron E. Carroll .
John Carroll : Next steps will be in preparation for 2014 when Affordable Care Act kicks in . Carroll : Most states will probably commit to participating in the Medicaid expansion . He says forming health insurance exchanges will be a lot of work to get ready . Carroll : For the costs of health insurance to continue getting a lot of attention .