Perez Hilton — The reign of of Katy Perry is over! (But don't fret- three weeks is quite an accomplishment!) This week's Billboard charts has a new #1 artist - Bruno Mars! Taking down Katy with his hit Grenade is an accomplishment in itself, but Bruno is the first ... more info

Guardian Music — Your percentage by percentage guide to the year in pop15% At the disco!"So we back in da club" Usher DJ Got Us Fallin' In Love"I'm in the club so I'm gonna do, do, do, do . . ." Taio Cruz Dynamite"Messin' with the baddest chicks in the club" Black Ey... more info

411 Mania — And Katy Perry and Bruno Mars benefit most from it... more info

ContactMusic — BRUNO MARS will start 2011 as America's pop chart king - his GRENADE has blasted KATY PERRY's FIREWORK off the top of the Billboard Hot 100.Perry falls to two as both top tracks make history as digital downloads, scoring two of the biggest sales week... more info

411 Mania — "Grenade" tops Katy Perry's "Firework"… more info

Reuters — NEW YORK (Billboard) - Bruno Mars ended Katy Perry's three-week reign on Billboard's Hot 100 singles chart on Wednesday, rising one place to the top with "Grenade," his second No. 1 hit as a lead artist. more info

Perez Hilton — iTunes is pretty happy Santa bought gift cards in bulk this Christmas! Music sales were at an all-time high this week on iTunes and astoundingly in CD stores. The big winners of the week in sales were Katy Perry and Bruno Mars, whose recent singles F... more info

Mjsbigblog — Dance jams filled the Hot 100 during 2010, and DJ Earworm takes the Top 25 songs from the year end Billboard Hot 100 chart to make a glorious mash-up of your favorite auto-tuned, beat- filled pop songs. Are your favorite songs samp... more info

Perez Hilton — What a year! As we are winding down 2010, take a look back at some of our highlights of the past 12 months (above). We did sooooo much! Thanks Nicki Minaj, Selena Gomez, Nicole Scherzinger, Jenny McCarthy, Nelly, Adele, Bruno Mars, Gloria Estefan, Le... more info

Reuters — NEW YORK (Billboard) - Katy Perry's "Firework" led Billboard's Hot 100 singles chart for a third week, while Bruno Mars' "Grenade" moved up one to No. 2 and was in prime position to take over the No. 1 slot next week. more info