The discrepancy of the favored indicator before and after the match is listed as a known bug in the blizzard forums by a message from Blizzard Employee Huginncord (Quality Assurance) in the thread "Known Issues 1.4.3 [Updated: 4/11/2012]"

• Favored messaging in the load screen sometimes doesn't match the favored messaging in the score screen.

We're investigating reports regarding inconsistent messaging in regards to the Favored status of player teams on the load screen when compared to Favored status on the Score Screen. Thank you for your patience while we look into potential causes for this inconsistency.

source: http://us.battle.net/sc2/en/forum/topic/2267599524

The discrepancy of the favored indicator before and after the match is listed as a known bug in a message from Blizzard Employee Huginncord (Quality Assurance) in the thread "Known Issues 1.4.3 [Updated: 4/11/2012]" on the blizzard forum.

The exact quote is as follows:

• Favored messaging in the load screen sometimes doesn't match the favored messaging in the score screen.

We're investigating reports regarding inconsistent messaging in regards to the Favored status of player teams on the load screen when compared to Favored status on the Score Screen. Thank you for your patience while we look into potential causes for this inconsistency.