Chart Juice: Rihanna, Usher Roar Into Top 10

Rihanna shows off her, um, assets and her dance moves during a collaborative set alongside Coldplay, during which she performed "We Found Love" with her army of raver back-up dancers.

R ihanna and Usher both bound into the top 10 on Billboard's R&B/Hip-Hop Songs chart with their equally-young, fast-rising new hits.

Rihanna's "Birthday Cake," featuring Chris Brown, earns the chart's Airplay Gainer badge as it moves 17-7, while "Climax" by Usher surges 18-10. Each song is in just its fourth week on the ranking.

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Rihanna's ninth top 10 on the tally becomes her fastest-climbing as a lead artist, while equaling her four-week top 10 jaunt as a featured artist on T.I.'s "Live Your Life" in 2008. For Usher, "Climax" marks his quickest top 10 ascent since "Papers" also reached the upper tier in four weeks in 2009. His "Nice & Slow" (1998) remains one of only 10 songs in the Nielsen era (since Dec. 5, 1992) to debut at No. 1.

The Rihanna/Usher explosions breathe life into the chart's upper reaches, as the top four remains unchanged from last week. Beyonce's "Love on Top" continues to reign supreme, with 33 million in audience (down 9%), according to Nielsen BDS. Drake's "The Motto," featuring Lil Wayne, holds at No. 2; Chris Brown's "Strip," featuring Kevin K-MAC McCall, stays at No. 3; and, Wale's "Lotus Flower Bomb," featuring Miguel, remains at No. 4.

Tyga's "Rack City" lifts 6-5 to become his first R&B/Hip-Hop Songs top five as a lead artist. Chris Brown's "Deuces," on which Tyga was a featured act, claimed the No. 1 spot for nine weeks in 2010.

Trey Songz's "Sex Ain't Better Than Love" climbs 7-6 on R&B/Hip-Hop Songs; "Make Me Proud," Drake's Nicki Minaj-assisted track, sinks 5-8; and, Melanie Fiona's slow jam "4 AM" steps back to No. 9 from its No. 8 high point. Fiona receives better news, however, lower on the chart: at No. 91, she debuts new bonus track "6 AM," featuring T-Pain. Her "4 AM" and T-Pain's "5 O'Clock" were the inspiration for the cleverly-titled blended tune, which will appear (with "4 AM") on her sophomore set, "The MF Life" due Tuesday (March 20).

SHH! QUIET CHART: On R&B/Hip-Hop Albums, Drake returns to No. 1 (2-1) with "Take Care," the chart's Greatest Gainer (58,000 units, up 97%, according to Nielsen SoundScan), and Lil Wayne's "Tha Carter IV" reappears in the top 10 at No. 2 (11-2), both due to last week's 25-cent album promotion by Google and AmazonMP3.

Otherwise, the chart lays rather stagnant, as it's the fifth time this year that no albums have debuted in the top 40. So far in 2012, 17 albums have started in the top 40, equaling the number seen in the same time span a year ago (on the charts dated Jan. 8-March 26).

Of this year's 17 top 40-starters, only three were R&B, while the rest have been rap sets. And, all three of the R&B albums have been covers efforts of older tunes. A year ago at this point, there was a more eclectic group of debuts, as seven of the 17 were R&B, and none were covers sets. With upcoming releases from Melanie Fiona's and Bei Maejor, the chart's woeful lack of R&B may be somewhat alleviated.

"Project X," the original motion picture soundtrack of the movie released in theaters on March 2, makes its way up to No. 3 from No. 6 in its second week. The various artists album is a compilation of tracks including those by Pusha T, J-Kwon, Nas, Kid Cudi, Wale, Dr. Dre & Snoop Dogg and Machine Gun Kelly. It shoots up by a healthy 43% with 24,000 sold.

Last week's R&B/Hip-Hop Albums No. 1, Tyga's "Careless World: Rise Of The Last King," descends to No. 4 (22,000, down 41%), while Rihanna's "Talk That Talk" rounds out the top five.