Today We Celebrating of A Song Smashed The Billboard Charts for 7 Weeks in Row 
Back In 2006,  Here is what was significant about "Sexyback:"

  1. New Sound - Unlike the clean blend of R&B and pop that Timberlake used on hisJustified, the FutureSex/LoveSounds album had a harder, dirtier sound. "SexyBack" is the dirtiest of the songs on the album. The bass is heavy. The vocals are distorted. JT doesn't sing in falsetto. The punchy riff is like electropop mixed with rock. In interviews, JT describe his new sound as "club funk," a mix of funk, pop, New Wave and rock. [1]  He filtered the influences of Prince, David Bowie, David Byrne and James Brown into one place, and it worked.

2. Sexy - "Sexyback" was JT's statement that he is sex symbol rather than a pop heartthrob. With lyrics like "You see these shackles? Baby I'm your slave." and "I'll let you whip me if I misbehave," there's no mistaking this is a sex song, not a love song. This was deliberate. Timberlake felt that radio music had gotten bland and was lacking in anything remotely sexy. Hence the opening lyrics, "I'm bringing sexy back" 

3. Explicit Lyrics - This was Justin's first single to have a Parental Advisory sticker. It wasn't just for the talk of whips and chains. There are curse words in the song. Though the words were edited for the radio, he does say "I'm bringing sexy back/ The mother f**kers don't know how to act," and "You mother fuckers watch how I attack." For a non-rap song designed to be played on pop radio stations, this was very unusual. 

4. Refocus - After Justin Timberlake released Justified, he was experiencing major burnout with music. This is a part of the reason why he began acting in movies likeAlpha Dog, Edison Force, and Black Snake Moan. His motivation to return to music was to make something that sounded different from the pop/R&B music he had already done. After meeting with Timbaland, he found a producer/partner who could help him steer his career in a new direction. The new song and album allowed JT to reinvent himself and regain focus on his music career. 

Danja, the producer extraordinaire talks about the Making Of Justin Timberlake's Hit "SexyBack"

DANJA: "For 'SexyBack' We were vibing in the studio. The way those sessions went, we jumped right in. The first record we did was 'What Goes Around Comes Around' and then we hopped into another idea. Me and Timbaland were jamming in the studio and Justin was there. We were recording while we were busting riffs, melodies, and beat patterns.
"There was maybe 45 minutes to two hours of us just jamming and they turned into songs like 'SexyBack,' 'Summer Love,' 'Sexy Ladies,' and another track. We went back, fine-tuned them, and make them songs. Everything we did in those sessions ended up on the album except for one song. Everything else, we made it on the spot and ended up on the project. There was no leftover songs from theFutureSex/LoveSounds sessions except for maybe one."
Justin Timberlake & Timbaland On The Of "SexyBack" (2006)
Though all of this is was a major departure for Justin Timberlake in 2006, I can't quite call it a major revolution for pop music. In fact, this track wasn't even a revelation for 2006. One month before "SexyBack" was released, Nelly Furtado released "Promiscuous," the lead single from her third album, Loose. Like "Sexyback," her song was:

  • Produced by Timbaland and Danja, and featured Timbaland as a guest vocalist. Like FutureSex/LoveSounds, her entire album was produced by Timbaland.
  • A new sound. It was a departure from her usual blend of pop, bossa nova, hip-hop and rock. "Promiscuous," like "SexyBack," it was dance song.
  • Sexy. I mean, the song is about two people flirtatiously talking about sex.
  • Had risque lyrics: Promiscuous doesn't have curse words, but the lyrics were very racy for the radio.