After their longest season yet, it was down to a college a cappella group, a hip hop group and a group creating an electronic dance club sound on the season finale of 'The Sing-Off' (Mon., 8PM ET on NBC). It was amazing watching these three powerhouse groups through the season.

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The Dartmouth Aires soared under the powerful lead vocals of Michael, while it took Urban Method a little while to find their strengths beyond their rap niche. Pentatonix struggled a bit with deciding how far to take their signature remixes. But all three groups excelled and impressed week after week.

In anticipation of next week's live finale, the phone lines opened for the first and last time on this longest-ever season of 'The Sing-Off' (Mon., 9PM ET on NBC). But before fans could decide who should win this season, the competition had to lose one final act.

It was a brutal night to be facing elimination, so close to the final, and you could see nerves throughout the evening as no one had a flawless night. Nevertheless, the judges based their decisions on what we've seen all season long, including tonight's double bill of a mastermix combining two songs and a judges' choice song.

After challenging the groups with hip-hop, 'The Sing-Off' (Mon., 8PM ET on NBC) threw them a double-whammy this week by having them tackle one song in the classic rock genre and another in country. It was a challenge that would truly show who could be the most versatile.

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Urban Method was probably the group most people were immediately concerned about, as neither genre suits their sensibilities. In fact, they even added a rap to their rock track, 'Here I Go Again,' which was a little odd.

This week, the seven remaining contenders on 'The Sing-Off' (Mon., 8PM ET on NBC) were tasked with creating superstar medleys, and no group faced a more daunting challenge than the Dartmouth Aires.

Now, they've got an outstanding frontman, but no-one is Freddie Mercury, and they had the task of bringing the music of Queen to life a cappella. For sure, this was going to be a performance the judges would scrutinize and hold their breath during.

The them may have been hip-hop, but one group went for a far more intimate and personal connection on 'The Sing-Off' (Mon., 8PM ET on NBC). To honor the recently-deceased father of one of its members, Vocal Point performed 'I'll Be Missing You' as a tribute.

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The performance was wrought with emotion, and the group slipped through to safety in the first bracket of the night. In the second group, the YellowJackets didn't muster enough with their take on Lupe Fiasco's 'The Show Goes On' and had to face off against The Collective, who didn't pull it together enough on Pitbull's 'Give Me Everything.'

It was Guilty Pleasures night on 'The Sing-Off' (Mon., 8PM ET on NBC) and Ben Folds certainly got into the spirit of the theme. While his professional work has never delved into hip-hop or rap, Urban Method's take on Bell Biv Devoe's 'Poison' inspired him to lay down some rhymes.

Maybe he was just excited that all ten remaining groups were finally together in the same week -- we know we were! Or it could be that Urban Method absolutely killed that performance, proving once again that a cappella can do anything, and sometimes the most unexpected directions bear the most exciting fruit.

One thing we did learn. While we applaud Folds for digging very deep and finding his inner MC, he should probably stick to singing. It seems to suit him better.

The idea of 'The Sing-Off' (Mon., 8PM ET on NBC) is that we get to hear songs like we've never heard before. This week, for doo-wop group North Shore, it was a chance for them to sing a song they'd literally never heard before.

The old school a cappella group admitted that none of them even listen to the radio anymore, so they didn't know who Bruno Mars was before they got assigned his hit 'The Lazy Song.' Nevertheless, they presented a version of the song that was true to the original, and yet sounded completely theirs.

There were a lot of great performances in this fourth week of 'The Sing-Off' featuring six of the remaining twelve acts. We can't wait for these brackets to unite into a single group of finalists so we can see everybody every week, though!

On 'The Sing-Off' (Mon., 8PM ET on NBC), we flipped back to the first bracket, which featured stand-out supergroup Delilah in the first week of the competition. But could they match their stellar vocals on 'Grenade' when featuring other members of the group on lead?

This week, the six remaining contenders in this group had to sing two songs each. First was a contemporary pop song followed by a classic hit from the 1960s. Things were switched up quite a bit this week, with some new voices rising to the top, and one group falling short.

Ben Folds joined Hoda Kotb as the guest host on the fourth hour of 'Today' (9AM ET on NBC) where he talked about what sets 'The Sing-Off' apart from other reality music shows and demonstrated his harmonizing skills by singing an improvised jingle made up of the notes on Hoda's cue cards.

"I think this show is socially significant. Music education has been on the down, and filling the space has been kids singing at colleges. There are about 4-8 A capella groups at each university now," he said." As for the show's contestants, he explained, "they're not divas. This show isn't about egos, it's people working together."

New 'The Sing-Off' judge Sara Bareilles co-hosted the fourth hour of 'Today' (weekdays, 9AM ET on NBC) while Kathie Lee Gifford was off shooting her 'Hot in Cleveland' cameo. Bareilles, who's a sweetheart by nature, talked about the challenge of giving singers negative feedback, sang some a capella of her own and hoola-hooped with Hoda.

Bareilles struggled to figure out how to provide substantive criticism without coming off like a jerk. "It's hard to be critical sometimes. I see that now as I'm watching the show be aired, and I remember feeling self-conscious about wanting to point out places where they need to make improvements," she said.

Youthful a cappella group Pentatonix gave it their all and wowed the crowd on 'The Sing-Off' (Mon., 8PM ET on NBC) last night.

The Los Angeles-based group performed their unique take on Katy Perry's song 'E.T.' and afterward seemed real happy with how it went.

Judge Sara Bareilles told the singers how she loved that each member of the group "had your little moment in that song where you just go to shine and to sparkle and we got to see all the dimensions of you."

With FOX having two singing competition shows on the air now to balance their schedule, NBC unexpectedly found themselves able to mirror that winning formula. With 'The Voice' waiting in the wings for a 2012 return, the network debuted an expanded third season of 'The Sing-Off' (Mon., 8PM ET on NBC).

With its emphasis on a cappella singing groups, 'The Sing-Off' manages to stand separate from its competition in bringing us vocal performances you simply can't see on any other show. Even 'The X Factor' with its group performances doesn't seem likely to get as involved as some of these groups do.

NBC's A cappella talent competition 'The Sing-Off' returns for a new season tonight at 9PM ET. Host Nick Lachey made an appearance on 'Today' (9AM ET on NBC) to talk about the judging changes the show has made this season, and the inspiring musical atmosphere the show fosters. It's so contagious that Lachey has been working in the studio on a new project of his own.

'The Sing-Off' will have a new judges this year, as Sara Bareilles joins Ben Folds and rest of the crew. It will also have a longer season, as its moving to 16 episodes. Lachey said the new judges bring a wealth of energy, and experience, to a set that's already brimming with its own unique vibe. The show has struck such a nerve that not only is it creating A cappella groups as part of the competition, but singers are starting to form their own groups to compete for a spot in the competition.

It's almost time for your favorite shows to return with all-new episodes, but why wait until September to see new footage?

Below you'll find the new promos for NBC's 'The Sing-Off,' Fox's 'Fringe' and CBS's 'Hawaii Five-0.'

'The Sing-Off' video from E! Online features new judge Sara Bareilles in action and tons of talent.

The 'Fringe' promo -- thanks to Give Me My Remote for pointing it out to us -- has Walter sitting in front of a bunch of speakers, listening to music when suddenly -- well, just watch.

And last but not least, 'Hawaii Five-0' features new footage of the team and McGarrett's mentor John Locke 'Lost' star Terry O'Quinn.

Excellent news for fans of smart, funny television for teens: MTV has ordered a second season of its newest scripted series, 'Awkward.'

Written by Lauren Iungerich, the show follows an outcast teen who rises in popularity after an accident leads everyone to believe she tried to kill herself. Awkward. The first season is currently airing Tuesday nights at 11PM following 'Teen Mom.'

MTV's first original series, 'The Hard Times of RJ Berger,' was canceled last week after two seasons.

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