Easy to read, but now somewhat outdated & incorrect in some cases. For example-
1. IMPB (Independent Medicare (not "Medical" as author cites) Advisory Payment Board) does indeed have real power. Unlike author's claim, under Sec 3403b Congress must pass legislation to STOP (not implement but STOP) IMPB spending limit proposals. Sec 3403b3 states Sec of HHS is required to implement IMPB's proposals "...UNLESS (emphasis added) Congress enacts legislation pursuant to this section."
2. In practice you are NOT able to always keep your current HI Plan if you wish. Current Plans are already being involuntarily changed due to ACA (e.g. Many Medicare Advantage plans, private Plans not covering birth control, etc.).
Medicare Advantage plans expected to increase by 7 percent in 2013 | Healthcare Finance News
Hobby Lobby files appeal in battle against ObamaCare contraception provisions | Fox News
3. In view of many ([mod edit]) ACA is indeed requiring coverage for certain abortions (e.g. drug-induced AB's with not only morning-after pills but weeks-after pills).
I could go on, but bottom line is NO ONE knows how this will all turn out. Sec of HHS has great power to alter implementation features (e.g. through delaying deadlines, waivers, etc.), Courts will still weigh in on various details, and future legislation will shape things too.