I'd be interested to know where the proof is that the increase in healthcare costs since AHCAA was passed are due to the act and not just the normal ridiculous growth in healthcare costs.
That said, clearly the provision that denies insurers the ability to deny coverage based on previously existing conditions is going to increase costs because those are individuals are known to have conditions that are going to cost the insurance company something. I guess the provision allowing children to stay on their parents plans might raise costs if the premium for dependents is less and/or the dependent is more likely to need healthcare.
On the savings side, however, there is a percentage of the population that could be paying at least some portion of their healthcare costs instead of waiting until things get so dire that they can't pay for hospitalization and declaring bankruptcy after the fact. Those costs get passed on to the majority of the population that does have insurance by the healthcare providers. There is some evidence from studies involving state run medicaid that having health insurance does in fact reduce the incidence of larger issues, so if that carries forward with AHCAA there will be some savings there too.
Clearly if things pan out in the increased cost or reduced cost category remains to be seen. There are good arguments for both cases. This act will help get people insured. That's a good thing. Insurance is just one part of the overall cost equation. More will probably also need to be done about constraining the cost of the healthcare itself of which the uninsured are just one small part.