To the shock of many and the delight of Rockefeller Center, NBC is finishing November sweeps at the top of the broadcast network ratings heap for the first time there in almost a decade. Rising from being the fourth-place network (meaning the worst, because The CW simply does not factor in) just last year, NBC scored an average 2.8 rating in the 18-49 demo, aka the only demo that matters, significantly higher than number two network CBS, which came in at a 2.4. CBS still has the highest average of total viewers of course, and actually ABC beats NBC in that department too, but those are all old people and nobody cares about old people. Where it counts, NBC is ahead. Can it stay that way?

Eh, that depends entirely on The Voice. And we do mean entirely. Sure freshman shows like Revolution and Go On have been modest successes for the Peacock, but it's really America's cheesiest singing competition that has brought all the boys and girls ages 18 to 49 to the yard. Everyone loves that damn show, and its strong numbers are propping up the rest of NBC's schedule throughout the week. It's so integral to certain shows' success that, for example, Revolution is taking a hiatus until March so it can start back up when a new season of The Voice begins. This model makes some sense (look how Fox coasted on American Idol for nearly ten years) but  we think NBC might be focusing too heavily on one show, and burning its fuel a little too quickly.

For one, The Voice doesn't have the numbers that American Idol enjoyed at its peak. It's a big hit, but it's not the biggest hit. And Idol only comes on once a year. Sure every season runs for five grueling months, but then it's done. The Voice, on the other hand, has already had three seasons, and it only premiered in April of 2011. NBC is hoping to keep viewers on their toes by shaking up the judges panel for its upcoming fourth season — swapping out Christina Aguilera and Cee-Lo for Shakira and Usher — but it's still going to be mostly the same show. How soon until viewers get tired? Also, will it matter that not a single human alive remembers the names of the two people who have already won the competition? There has yet to be a Kelly Clarkson or a Carrie Underwood to kick the show into the realm of credibility, so it remains mostly a novelty act. And how much juice does a novelty act really have?

The problem is, if The Voice starts to falter, then NBC really doesn't have much that could come to the rescue. What, is the retooled second season of Smash going to start doing boffo box office? Will Up All Night's switch to multicamera make it the Friends of the twenty-teens? It's doubtful. When Revolution's just-OK numbers are considered a hit for the network, it means everything else is doing pretty meagerly. So pop the cork on one bottle of champagne, NBC. But save the rest of the case for when you figure out what to do after The Voice goes silent. Because if you don't, it's going to be a pretty quiet, and pretty quick, fall back down to the bottom.