Below is a google doc of the statistics of every extended series that has occurred in SC2 MLG history up until this moment.
Google Doc
Some interesting statistics:
There have been 61 extended series prior to the match between DRG and MKP
47(77.0%) of extended series were won by the winner of the first series. Only 14*(23.0%) of the losers of the first series went on to win.
In 26(37.7%) of extended series, the original loser did not win a single map in the second series.
Only 4 times when the original series ended 2-0 did the loser of that series go on to win the extended series.
The Player who lost the first series won more maps in the extended series 61.7% of the time.
The loser of the first series lost the extended series while winning 2 or more maps in the extended series 7 times.
If anyone wants to check over my work go ahead, but I've double checked the numbers and such.
*- The match between Whitera and epGimix was not included for obvious reasons.
**Edited for awkward wording.