Initially released as a promotional single, the song titularly refers to the informal contraction imma.

Eric Henderson from Slant Magazine stated that in the song, "halfway through, the pulse gets an upgrade, the tempo hustles up to a strut, the rudimentary synth hits explode into a chunky-funky rush, and before you know it, will.i.am has transformed a deliberately lazy self-parody into a heated club-floor burner.

[2] PopMatters gave the song a positive review: "Highlights of the album include 'Imma be', which despite the repetition of the title no less than 105 times...takes a really interesting path from hip-hop attitude to club hit to jazz romp that holds up well to repeated listens".

[4] Billboard said "The group sounds as unabashedly confident as ever here.....A brazen horn section and smooth keyboards cruise along until the song's sudden transition, when the beat switches from a snap music-meets-Neptunes stomp to a funk-house glide, meshing with a seemingly endless vocal loop of 'Imma be' to form a pounding, assertive club thumper.

It was later released as the fourth single from the album in the U.S. and became the group's third number one hit on the Billboard Hot 100 for the week ending March 6, 2010 and halted the nine-week run of Kesha's "Tik Tok".

The clip features Fergie wearing Louboutin designer footwear and a black metallic leotard and riding a BMW S1000RR motorcycle.

After the other members protest against the device's use, Fergie walks out of the studio in frustration and rides off in a motorcycle only to get hit by a car.

The "Imma Be" video then begins with Fergie, following her accident, waking up on a road in a desert where she notices everything stuck on a loop.

apl.de.ap brings a good white robot to life as they dig through the scrap and find Taboo whose bottom half of his body is missing.