Primetime was to combine a TV gameshow-like experience with the interactivity of games across Xbox Live. Players would be eligible to win real world prizes.
But now the feature, which could do wonders in Microsoft's bid for the mainstream gamer, won't be available until this coming spring.
The TV show 1 vs. 100 was to be the first gameshow to be adapted for Primetime, with scheduled events bringing connected gamers together in one virtual place.
Microsoft's Aaron Greeberg told Forbes Microsoft is still committed to Primetime despite its delay.
The New Xbox Experience is a free update for Xbox 360 that Microsoft says will improve the console's accessibility with a revamped interface and new community features.