O'Driscoll told Off The Ball, "I think a series victory in New Zealand is greater than a semifinal of a World Cup. [Ireland has never advanced beyond a quarterfinal at World Cups]
"It's something tangible…there is something at the end to hold onto, to be able to go, 'by the way, we beat New Zealand in their own backyard', versus 'we did great, we got to a semi final'," he said.
But he also felt a more balanced argument would be getting to a World Cup final as opposed to a series victory.
"Going into a World Cup final with it still to play versus a series victory against the All Blacks – I think that's more on par," he said.
O'Driscoll acknowledged the All Blacks had not lost a Test series at home since 1994, and that was important when considering the job Ireland had in front of them.
While the prospect of a series victory had raised interest in Saturday's third Test in Wellington, in both countries, it was also important because opportunities for Ireland's players to get game time ahead of next year's World Cup were running out fast.
"This is still enormous in its own right, but it doesn't mean that there isn't going to be another missed opportunity for guys to get game time, and those games are running out," he said.