From the Senate record, the bill voted on on December 24, 2009 was HR 3590.
http://thomas.loc.gov/cgi-bin/bdquery/z?d111:HR03590:
H.R.3590
Latest Title: Patient Protection and Affordable Care Act
Sponsor: Rep Rangel, Charles B. [NY-15] (introduced 9/17/2009) Cosponsors (40)
Related Bills: H.CON.RES.254, H.RES.1203, H.R.362, H.R.2358, H.R.3688, H.R.3780, H.R.4204, H.R.4872,
S.1239, S.1423, S.1728, S.1790, S.1857, S.1959, S.2964
Latest Major Action: Became Public Law No: 111-148 [GPO: Text, PDF]
Note: H.R.4872 makes a number of health-related financing and revenue changes to this bill. Read together, this bill and the health care-related provisions of H.R.4872 are commonly referred to as the Affordable Care Act (ACA).
Jump to: Summary, Major Actions, All Actions, Titles, Cosponsors, Committees, Related Bill Details, Amendments
SUMMARY AS OF:
3/23/2010--Public Law. (There are 3 other summaries)
(This measure has not been amended since it was passed by the Senate on December 24, 2009. The summary of that version is repeated here.)
(There is far more detail in the above link.
Both the House and the Senate passed health care bills. When the Senate bill put its together, they took the already passed House bill that was sent to the Senate and passed the Reid amendment to the House bill 3590 - which was in the nature of a substitute. (ie this substituted the Senate bill for the House bill. This was done on Dec 23, 2009.) Look at the Reid Amendment on Dec 23 -
http://www.senate.gov/legislative/LIS/roll_call_lists/vote_menu_111_1.htm
Then because the Senate amended the bill, two things could happen to get a unified bill and send it to the President. The most normal is that both sides select conferees and they produce a compromise bill that must then pass both the House and the Senate. The election of Scott Brown made this impossible or at least highly controversial (if they rushed it through with Kirk still voting because Brown was not yet seated.) The second option was for the House to pass the newly passed Senate bill without changing even a comma! This could then be sent to Obama for signature because one identical bill was passed by both houses.
To make things more complicated and to make some "corrections" to the main bill, a deal was made with the more liberal House that a second much smaller bill would then be passed that included some changes and a major education bill. That bill started in the House as an amendment to the budget bill. As it was on a budget bill AND it did not increase the deficit, it only needed 51 votes in the Senate. Here, it seems no one is questioning this side bill.