The health care bill makes it compulsory for all Americans to buy private insurance in the free market which in and of itself is an incredible irony. What's so free about a market where you are forced to buy something? There are many who don't think the solution that passed is Constitutional because while the government has the right to tax, it does not have the right to force citizens to buy a particular product. As Robert Siegel pointed out on NPR recently, It's even more ironic that a public plan would have been perfectly Constitutional, because like social security and medicare it would have been funded through taxation. The flip side which I haven't heard discussed is that long ago we made it mandatory for hospitals to provide emergency care to people that have no insurance. So we already have a situation where a private firm is legally required to provide a service for free. That certainly seems just as bad as requiring everyone who could potentially require that service to pay some nominal fee upfront. In fact, the health care bill may even correct that injustice. Except of course, that it doesn't, because the new bill does not cover folks in this country illegally whom the Emergency Room staff are still obligated to help.
I personally favored a solely public plan solution (also called "single payer") which would have removed private insurance carriers entirely. A single payer system would have removed the middle man and covered everyone in the country - saving perhaps billions of dollars, simplifying an otherwise onerous accounting process for doctors and hospitals and allowed for national standards to be set for provided care. The big losers in this would have been the insurance companies. Insurance companies are essentially bookies that are betting you aren't going to get sick while you're betting you are. Their actuaries are usually right (luckily for them) which means much of the money they take in is profit and does nothing to either improve care or provide it. They have no incentive to improve care (which is expensive), but lots of incentive to deny it or cancel it.