The 'X Factor's final 12 contestants really kicked it into high gear on tonight's episode during the opening performance of David Guetta and Usher's new single 'Without You.' The high energy performance began with R&B cutie Marcus Canty and former burrito craftsman Josh Krajcik emerging from the darkness singing the opening lines, "I can't win, I can't wait / I will never win this game without you, without you."

As the remaining 10 acts joined in on the action in a 'Glee'-like performance, we have to applaud the final 12. They've never sounded better. The audience was out of their seats and dancing along. Isn't that what good music is supposed to do?

Though the performance as a whole was fun and full of energy, there were some clear weak links. Last night Cowell called Intensity's performance of 'Kids In America' "terrific," which leaves us wondering what exactly Simon is hearing. If those kids are the future of the music business in America, we're running for the hills.

We must also note that rap phenom Brian Bradley/Astro flubbed his verse on this opening performance. And though Paula Abdul told him that Jay-Z was keeping an eye on him, we've never heard a instance of HOV forgetting the lyrics to one of his songs. Perhaps Brian is going through some growing pains of performing. We certainly hope so -- because he's entertaining, darn it!

The opening performance gets two big thumbs up. As all the acts sang together, we could only hope they'll take this show on the road for an 'American Idol'-esque tour after this debut season of the 'X Factor' raps up.

Watch the 'X Factor' Group Perform 'Without You'