Today the SCOTUS ruled that Obamacare is constitutional. I am not a lawyer and don't claim to understand whether or not it is a good ruling. My gut says "yes," but that is an opinion without any real basis so take it with that degree of impact.
Whether or not the law is constitutional has nothing to do with whether or not it is a good law and there are those on the right and the left who are arguing that it is not a good law. Those on the right say that the law interferes with the movement of the free market and impacts the freedom of individuals. Those on the left argue that health insurance is too important to be subject to the whims of the free market and should never be a for-profit business and that this law will make the movement towards establishing a non-profit, single payer system more difficult to accomplish.
I hoped for at least the option of a single payer system all along and in the best of all worlds, that is what Obamacare would have been. I'm not sure how this law will impact that possibility. There are those who argue that the constraints on the private insurance companies included in this law will drive them out of the health insurance business and push us towards single payer. Others argue that this law just entrenches the for profit health insurance companies which will keep us from moving towards single payer. Time will tell.
The Republicans will vote to repeal this law although, it isn't clear that they would do this if they really had the power to make it happen. Being seen as responsible for removing the popular provisions of this law is not likely something they really would want and keeping the popular provisions without the individual mandate is not something the insurance companies are likely to be happy about...