Chart Beat Thursday: John Mayer, Folk Albums, David Guetta
John Mayer Albert Watson

VIDEO THRILLED THE RADIO STARS: Katy Perry brings the MTV "Unplugged" brand back to the Billboard 200 after two years, as "MTV Unplugged (EP)" arrives at No. 168.

Perry's album is the 27th edition from the series to dent the chart dating to the first on the list dated June 22, 1991.

Here is a chronological checklist of all the show's soundtracks to reach the Billboard 200:

1991, No. 14, Paul McCartney, "Unplugged - the Official Bootleg"
1992, No. 3, Mariah Carey, "MTV Unplugged EP"
1992, No. 1 (three weeks), Eric Clapton, "Unplugged"
1993, No. 60, Arrested Development, "Unplugged"
1993, No. 2, Rod Stewart, "Unplugged ... and Seated"

1993, No. 71, various artists, "Uptown MTV Unplugged"
1993, No. 23, Neil Young, "Unplugged"
1993, No. 13, 10,000 Maniacs, "MTV Unplugged"
1994, No. 48, Tony Bennett, "MTV Unplugged"
1994, No. 1 (one week), Nirvana, "MTV Unplugged in New York"

1994, No. 97, various artists, "The Unplugged Collection Volume One"
1995, No. 23, Bob Dylan, "MTV Unplugged"
1996, No. 15, Kiss, "MTV Unplugged"
1996, No. 3, Alice in Chains, "Unplugged"
1997, No. 53, Maxwell, "MTV Unplugged EP"

1997, No. 189, Bruce Springsteen, "In Concert/MTV Plugged"
1997, No. 106, Babyface, "MTV Unplugged NYC 1997"
1998, No. 88, Bryan Adams, "MTV Unplugged"
1999, No. 83, Mana, "MTV Unplugged"
1999, No. 63, Alanis Morissette, "MTV Unplugged"

2000, No. 124, Shakira, "MTV Unplugged"
2002, No. 31, Jay-Z, "MTV Unplugged"
2002, No. 3, Lauryn Hill, "MTV Unplugged No. 2.0"
2003, No. 111, Dashboard Confessional, "MTV Unplugged V 2.0"
2005, No. 1 (one week), Alicia Keys, "Unplugged"

2007, No. 9, Korn, "MTV Unplugged"
2009, No. 168, Katy Perry, ""MTV Unplugged (EP)"

OH, BROTHER: In 2000-01, twin duo Evan and Jaron (Lowenstein) roared to No. 4 on Adult Pop Songs and No. 15 on the Billboard Hot 100 with "Crazy for This Girl."

This week, the younger half of the pair (by five minutes) joins the list of artists (Michelle Branch, Jewel and Darius Rucker, for example) who've segued from pop to country this decade, as Jaron and the Long Road to Love claims Hot Shot Debut honors on Country Songs with "Pray for You" at No. 58.

(Or, as Jaron told cmt.com, "I didn't go country. Country went pop.")

Since their breakthrough, Evan and Jaron (discovered by Jimmy Buffett), have hosted USA Network's "Character Road Trip" and released their last 'album,' 2007's "52 Sundays," a collection of cuts that the media-savvy siblings offered one-by-one online each weekend for a year.

CHART BEAT BITS: Norah Jones debuts on the Billboard 200 at No. 3 with "The Fall," her fourth studio set. Her prior three topped the tally, while "New York City," by the Peter Malick Group featuring Jones, peaked at No. 54 in 2003. The new album's first single, "Chasing Pirates," pushes 5-3 on the Triple A adult alternative airplay chart (viewable at billboard.biz) and 22-18 on Adult Contemporary ...

Reigning "American Idol" champion Kris Allen launches on the Billboard 200 at No. 11 with his self-titled debut album. The show's 2009 runner-up, Adam Lambert, debuts at No. 72 with "Take One," a set of pre-"American Idol" recordings. His proper introductory album, "For Your Entertainment," will arrive on next week's chart ...

Janet Jackson starts on the Billboard 200 at No. 22 with "Number Ones" (not to be confused with Michael Jackson's like-titled collection at No. 37). Billboard 200 chart manager Keith Caulfield notes that 30 of the 34 songs on Janet's new best-of set reached No. 1 on either the Billboard Hot 100, R&B/Hip-Hop Songs, Dance Club Play Songs or Adult Contemporary. It includes all 10 of her Hot 100 No. 1s and all 16 of her leaders on R&B/Hip-Hop Songs ...

Two of 2009's most buzz-worthy new acts shine on the Billboard Hot 100. The "Glee" cast bows with its updates of Bill Withers' "Lean on Me" (No. 50), the Police's "Don't Stand So Close to Me" paired with the Union Gap's "Young Girl" (No. 64), the Pretenders' "I'll Stand By You" (No. 73) and Lionel Richie and Diana Ross' "Endless Love" (No. 78). The troupe has charted 18 titles this year, second only among all acts to Lil Wayne (20) for most chart appearances in that span. Justin Bieber concurrently arrives with three songs. With their entrances, all seven tracks from his debut "My World (EP)," which opens on the Billboard 200 at No. 6, have hit the Hot 100 ...

Pre-Thanksgiving, the Chipmunks gnaw their way onto the Billboard 200 with "Christmas With the Chipmunks" at No. 73. With the album's appearance, the revered rodents extend their Billboard 200 chart span to 50 years and one week, dating to the entrance of "Let's All Sing With the Chipmunks" in November 1959.