Quoting from ECB's annual accounts (pdf, page 15):
The ECB's holdings of securities purchased under both programmes at the end of 2010 were
as follows:

 

                                  2010 €            2009 €               Change € 

Covered bond purchase programme   4,823,413,246     2,181,842,083     2,641,571,163

Securities Markets Programme      13,102,563,262           0           13,102,563,262

Total                            17,925,976,508    2,181,842,083    15,744,134,425

...
and comparing with their current position

which is probably an apples-to-oranges comparison (holdings/outstanding amount?)

So I got the wrong end of the stick, there has not been a massive buy-up of bonds by the ECB in 2011. They have either decided that the markets are correctly pricing the bonds (in contradiction with their "mark-to-book" policy), or have renounced market intervention (recognition that they are powerless?)

In any case, if the ECB holds €50B of Greek bonds, they were mostly bought in 2010, and that comes out to more than a third of the total of SMP holdings (75B) and CBP (60B), no?

_{It is rightly acknowledged that people of faith have no monopoly of virtue - Queen Elizabeth II}