"From the press releases, it appears that the old bond holders can choose to just keep them."
The Notes are redeemable in part or in full at the option of the holder on March 1 at each of 2013, 2018, and 2023, or upon fundamental corporate changes. They are also redeemable by the Company in part or in full on and after March 5, 2013
Redemption of the 2028 notes has been initiated.
On the new notes, interest is reduced, plus they have an extra 140 million or so in walking around money. The cost of carrying almost double the amount of new notes is not much more than the cost of carrying the old ones. The only benefit to new noteholders would be that the conversion price is 20 dollars instead of 43.33.
As to the stock price, all PM stocks are down, but recent Argentine economic conditions and political actions are affecting SSO perhaps more severely than others. Argentina today is not the Argentina of a couple of years ago - they are replaying the scenario that has been seen many times.