1. Most provisions (such as the exchanges, subsidies for the exchanges, ban on considering pre-existing conditions) goes into effectd 2014. Other select provisions (high risk pools, covering children, Medical loss ratios) go into effect earlier.
2. If your insurance plan covered dependents, it should now cover them until age 26 (starting September 23, 2010).
3. Yes. Medical loss ratios limit profits to insurance companies, which requires more premiums be spent on care (which reduces out of pocket expenses/etc.) There are various pilot projects to try to reduce costs in the bill, and the results of these will dictate whether the HHS continues them or expands them. These include things like paying for outcomes instead of the current fee-for-service model in Medicare. Often, private insurance uses Medicare reimbursement rates/procedures as a baseline.
For more detailed information on cost controls, go here:
http://voices.washingtonpost.com/ezra-klein/2010/03/the_five_most_promising_cost_c.html4. While the bill doesn't place direct price controls on hospitals, increasing the number of insured will reduce uncompensated care (and therefore reduce the reason why this inequity exists).