Britney Spears, Christina Aguilera

Which singing show will reign supreme this fall?

NBC's The Voice threw down the gauntlet when it expanded its planned two-night Monday-Tuesday premiere to a third night on Wednesday, which puts it head-to-head with the first night of The X Factor's two-night premiere. In response, X Factor creator and judge Simon Cowell deemed the move as "cold-hearted" and nothing more than "dirty tricks."

The Voice premiere expands to three nights to battle The X Factor

Name-calling and strategic programming aside, the real competition comes down to viewer appeal and retention. Which show's format is more compelling? Which Mickey Mouse Club alum will draw more eyeballs? Christina Aguilera on The Voice or new X Factor judge Britney Spears? Can Demi Lovato bring a younger audience to Fox? Did Cee Lo Green make a mistake by replacing mascot Purrfect with a pink cockatoo?

TVGuide.com assesses these factors and more in our side-by-side comparison of The Voice and The X Factor:

Mickey Mouse Clubbers
The Voice:
Aguilera's got the pipes — not to mention a shiny Grammy for Best New Artist. Her last record bombed and a public-intoxication arrest was unfortunate. Still, she's got two seasons on Spears, and her judging persona has been a lot of things, but never boring!
The X Factor:
Spears, the undisputed pop princess of the TRL era, is still a mega-star among fans who choose to ignore her Kevin Federline days (and that shaved-head incident). Early reports claim that she is a tough but fair judge. If all else fails, though, audiences love a TV train wreck.
Round 1:
Draw

Banter
The Voice:
Anyone who thought that Adam Levine and Aguilera's love-hate relationship was just for ratings got a big (and bitter!) taste of reality at the end of Season 2, when Aguilera took Levine's contestant, Tony Lucca, to task for singing lyrics that were derogatory toward women. Levine fired back at Aguilera, and many believed their feud affected the outcome of the finale. To your corners, judges!
The X Factor:
Every clip we've seen of newbie judge Lovato smacking down elder Cowell is, dare we say, charming? Even dour Cowell himself seems to like it, and we can't help wanting to see him be on the receiving end of more jabs since he's usually the one doling out the criticism. Take it, Grandpa!
Round 2:
The X Factor

Fashion
The Voice:
Levine's constant parade of offbeat T-shirts and Blake Shelton's classy country look are nothing to tweet about. Thankfully, Aguilera's copious cleavage, questionable head gear and apparent distaste for pants and Green's penchant for all that glitters renders The Voice stage into a veritable runway week after week.
The X Factor:
Lovato's quirky ensembles are intriguing, as is the pink streak in her hair, but she's alone in the fashion spotlight. Spears' look is surprisingly subdued, L.A. Reid wears nice suits (yawn), and we just can't be more depressed by Cowell's dreary parade of monochromatic V-necks.
Round 3:
The Voice

Simon Cowell on The Voice's additional night: NBC is playing "dirty tricks"

Inclusiveness
The Voice:
 The show has given second chances to older artists who have had past brushes with either a record contract (Javier Colon) or reality-show success (Frenchie Davis). However, The Voice's auditions preclude anyone under 15 or anyone in a group bigger than two — and so far, the battle rounds have been none too kind to the duos — remember this?
The X Factor:
The lower-age limit is 12, which means we can expect a completely younger sound and precocious appeal, as evidenced by Season 1's Astro and Rachel Crow. It's also more fun to see groups get through, and you just can't argue with the success of One Direction, a boy band that came in third on its season of the U.K.'s X Factor.
Round 4:
The X Factor

The Ryan Seacrest Wannabes
The Voice:
Carson Daly's many years spent wrangling unpredictable talent for MTV has proved to be fertile training ground for corraling the judges, particularly Aguilera. However, any good will earned by Daly is seriously diluted by the stiff, overeager social TV correspondent Christina Milian.
The X Factor:
The Fox show has been through so much hosting turmoil (two hosts, host-turned-judge, no hosts) that we're not sure if there will even be an emcee at all. And sorry, rumors that a Kardashian is a front-runner to host don't engender any confidence in us. No, we don't care which one it is.
Round 5:
The Voice

Judges' Versatility
The Voice:
Sure, it doesn't boast any behind-the-scenes talent on the judges panel, but unlike its competitors, The Voice's judges not only coach and critique the singers on their team — they perform right alongside them! The collaboration between mentor and mentee can only be topped by the electric group performances by all four judges.
The X Factor:
It's great that Reid and Cowell have some industry cred, but what else ya got? A little head-bobbing? There's something to be said about actually understanding what the contestants are going through performance-wise.
Round 6:
The Voice

Mascots
The Voice:
Green raised the stakes for Season 2 by introducing the world to his silent but sassy lap decoration, Purrfect the Cat. After Purrfect tweeted his way into fans' hearts, however, he was unceremoniously replaced by a pink cockatoo named Lady. Me-OW!
The X Factor:
Uh, does Lovato's furry coat count?
Round 7:
The Voice

Report: Khloe Kardashian is front-runner to host The X Factor

Dark-Horse Judges
The Voice:
Before the show's debut, Shelton was largely unknown outside of the country universe. But he pressed viewers' buttons from Day 1, thanks to his signature mix of sweet — his paternal affection for his singers is unrivaled — and sour — his critiques are some of the show's most honest.
The X Factor:
Who knew that both Lovato and Spears would be the feisty judges? Will they out-Cowell Simon?
Round 8:
The X Factor

Prize
The Voice:
The winner receives $100,000 and a recording contract.
The X Factor:
Cowell awarded a $5 million recording contract to last season's winner Melanie Amaro, who isn't exactly a household name yet, but there's still no denying that chunk of change.
Round 9:
The X Factor

Verdict: It's a tie -- 4 to 4 with one draw. As always, the viewers will have the last word.

The Voice premieres at 8/7c on Monday, Tuesday and Wednesday on NBC, while The X Factor premieres at 8/7c on Wednesday and Thursday on Fox.