In true Britney style, her new tour 'Femme Fatale' kicked off with elaborate costumes, lots of dancing, and piercing screams from the audience.

Whether you love or hate her music, there is no denying that the arguably most famous pop star (in the world) still has the power to attract millions of viewers and screaming fans.

RollingStone.com described the show as her flashiest, fastest moving, and most entertaining production yet.

The night belonged to Britney: She managed to prove that she's still progressing as a showgirl. Not only that, she's doing it better than even die-hard defenders would've predicted.

With 'Grease' inspired choreography, the song 'How I Roll' Britney looks like she's having a blast on stage with her dancers.

Britney also revives 'If You Seek Amy' and channels Marilyn Monroe with a Monroe-esque costume. Britney has publicly stated that she is a fan of Monroe, and when Tommy Hilfiger purchased three pairs of the late actress's jeans, Hilfiger gifted a pair to Britney who is the same height that Monroe was.

It seems Britney is aware that fans want to not only hear her latest music, but take a trip down memory lane with the music which made the pop star famous. Britney sings (live) her old ballad, 'Don't Let Me Be the Last to Know,' which was released in 2001 on her 'Opps! . . .I Did It Again' album. The song was written by Robert Lange, country singer Shania Twain and Keith Scott.

The singer also dances in cut-off jeans to 'Womanizer.'

And for those ready to criticize Britney for any of her dance moves in the 'Femme Fatale Tour,' Justin Timberlake has Britney's back. After a video went viral about the pop songstress, comparing her old dancing days to her latest moves, Justin defended Britney. Timberlake stated: I don't have too much to say about her situation. I can't remember the last conversation I had with her. But this thing that happens online bothers me - these anonymous commenters.

People think they can say anything, and it doesn't matter to people. I'd love to see the people who comment about Britney online say those things to her face, because they couldn't.

Also, in Britney's defense, if you pulled up a video I did from 2003, I couldn't do the sh*t I did then either.

Selena Gomez dished about Miss Britney on 'Good Morning America' when the young actress (turned pop singer) talked about working on a Britney song. She stated, I heard the song and I fell in love with it, I thought it was really fun and catchy, and I went into the studio and it said on the thing, co-written by Britney Spears, and I almost had a heart attack. Gomez also stated that she will be doing a Britney tribute during her summer tour.

The 'Who Says' singer will pay tribute to Britney with a medley of Brit's songs during the tour, including some off the 'Femme Fatale' album. Gomez told MTV.com that she is 'stocked' about the tribute. We're gonna do 'Baby One More Time,' and then I think we're going to try to incorporate 'Toxic' and that phase, and we might do some of her recent new stuff.

But Gomez blushed when asked if she is going to do any of Britney's dances and said, I don't think so, I'm not even going to touch Britney like that. I wouldn't butcher it. I'm just going to [do a] tribute to her because she's awesome.

In other tour news, Nicki Minaj, who is traveling with Britney as the opening act, will not be joining the 'Femme Fatale' tour when it travels to Europe. On her Facebook Page, Minaj wrote, I will not be performing with Britney outside of the US and CANADA. Sorry!

Watch behind the scenes with Britney on her set

Watch a clip from the live Sacramento tour

'How I Roll'

'If You Seek Amy'