After the Fed stops buying US bonds with the Monopoly money it is printing (June or so?) Will there be enough demand from other buyers to take up the slack. If not, then interest rates will head where everyone knows they need to go.(up!) 2008 all over again.
Given the amount of debt to be issued, the Fed has to print more money so Treasuries (new and rolled over) can be purchased. If they do not call it QE3, it will be called something else. Nevertheless, it is printing money. The music plays, the game goes on.