Justin Bieber's 'Boyfriend' single has finally dropped and it's pretty much the perfect pop song, as the singer and boy wonder has just hurdled the bridge between adolescence and adulthood and landed on his feet with a smile. The song, written by Bieber, Mike Posner and Mat Musto, finds The Biebs stepping into the shoes willingly vacated by Justin Timberlake while he pursues acting.

'Boyfriend' has a whisper opening, where Bieber assumes a hip-hop swagger and posture while delivering the lyrics. He's totally breathy and because of it, the song sounds much more adult than anything he's done previously. It's butter smooth, not to mention hot!

Then The Biebs pulls out the Timberlake-Michael Jackson falsetto when he hits the first chorus, when he sings about being "everything you want." Mmm hmm. He certainly picks up where those two pop legends left off and drops the higher pitched vocal style in the subsequent choruses.

All the verses are rapped, in that sexy style. Much has been made about The Biebs rapping, but relax -- he's not imitating the likes of Lil Wayne, being all hard. It's just that his cadence is very hip-hop in its pentameter and delivery, and it sounds uh-mazing. He's trying new things and the result is a more mature, more well-rounded Justin Bieber song.

The instrumentation is kept to a minimum, allowing The Biebs' voice, which has strengthened and deepened as he matures and grows up, to shine and take center stage. There are lots of claps and beats, which sound like they were picked up at the Pharrell Williams school of production! And you know what? Mike Posner's contributions to this song ensure that he is on the rise as a beat-driven producer and he'll be sought after once this song spreads like wildfire, which we can assure you it will.

Overall, 'Boyfriend' reminds us of JT's 'Cry Me a River' in texture and tone, especially with those layered harmonies.

There's a new Justin reigning over pop music domain and it's The Biebs. He's bringing sexy back and at just the right time.

Nab it here, Beliebers.

Listen to Justin Bieber, 'Boyfriend'