Sometimes you have to tank a bit to get your mojo back. After failing to grab fans with her second album, 2003's Folklore, Nelly Furtado is back on top with her third effort, Loose, which will debut at #1 on Billboard's albums chart, according to the latest SoundScan totals. Thanks to the ubiquitous Timbaland-produced hit "Promiscuous," Loose's week-one sales of 219,000 were more than enough to earn the singer her first #1 debut.

Florida metalcore band Underoath score a surprisingly high debut with the #2 ranking Define the Great Line, but fall well behind Furtado. The band sold 98,000 copies of its latest album to land Underoath their highest-ever chart position, nudging the Dixie Chicks' Taking the Long Way down a notch to #3. British piano-rocking trio Keane also slip in with a top-five debut, cruising into the #4 position with their second album, Under the Iron Sea, selling 75,000 to reach their highest spot on the U.S. charts.

Last week's #1, Busta Rhymes' The Big Bang, takes a big hit, dropping down to #5 on sales of 69,000 -- a 67 percent slip from the rapper's first-ever chart topping debut. The "High School Musical" soundtrack proves more resilient, slipping two spots to #6 after moving 66,000 copies for a week-to-week decline of just 17 percent.

Albany, Georgia, rap duo Field Mob debut in the top 10 for the first time with their third album, Light Poles and Pine Trees, which ranks at #7 with 63,000 units scanned. After seven weeks on the charts, Gnarls Barkley finally crack the top 10, climbing three spots to #8 with their debut, St. Elsewhere (58,000), while AFI's Decemberunderground drops six places to #9 (57,000). Rounding out the top 10 was the soundtrack to the animated movie Cars (56,000).

The Red Hot Chili Peppers drop out of the top 10 for the first time since their double album, Stadium Arcadium, was released seven weeks ago, landing at #13 with 54,000 in sales. Three Days Grace took a 55 percent hit, selling 35,000 copies of One-X, which plummets from #5 to #21.

There are plenty of chart debuts just outside the top 10, including R&B singer Donell Jones at #15 with Journey of a Gemini (49,000), critically acclaimed crooner Corinne Bailey Rae at #17 with her self-titled debut (40,000) and quirky rockers Guster at #25 with Ganging Up on the Sun (30,000).

Other releases cracking into the top 200 include the CD/DVD of Madonna's 2004 tour, I'm Going to Tell You a Secret, which makes a modest debut at #33 (25,000); the soundtrack to The Fast and the Furious: Tokyo Drift, which hits #40 (21,000); the Counting Crows live disc New Amsterdam - Live At Heineken, in at #52 (17,000); and You Hear It First subjects Cute Is What We Aim For, who make a solid bow at #75 with 14,000 sales of their debut, Same Old Blood Rush With a New Touch.

British power metalers Dragonforce land at #103 after moving nearly 10,000 copies of their third album, Inhuman Rampage. And old-school R&B stars are also represented on the top 200, with Smokey Robinson in at #109 with Timeless Love (9,000 copies sold) and Diana Ross taking #146 with Blue (6,000).

The week's biggest-gainer award goes to Oscar-winning rap crew Three 6 Mafia and their Most Known Unknown, which scored a nearly 250-percent bump. The album, which fell out of the top 200 on the last chart, jumps to #54 with 17,000 copies sold.