RIAA Tally: Update 2
Justin
"Under the Mistletoe" is currently Platinum!
"My World 2.0" rose to 3x Multi Platinum
"Somebody to Love" is Platinum!!
"Baby" Rose to 3x Platinum
"One Less Lonely Girl" went Platinum!
"Mistletoe", "Favorite Girl" and "Boyfriend" all went Gold! and "Boyfriend" is expected to go Platinum any day now!

Taylor
"Mine" rose to 2x Platinum
"Mean" and "Ours" both went Platinum!!
"Speak Now (SONG)" went Gold!
"Jump Then Fall" has also gone GOLD as well as "Sparks Fly"
"Speak Now (ALBUM)" Rose to 4x Multi Platinum
"You Belong With Me" rose to 4x Multi Platinum
"The Taylor Swift Holiday Collection" went Gold!

OTHER:
Selena: "When The Sun Goes Down" is GOLD and "Love You Like a Love Song" is 2x Multi Platinum
Demi: "Skyscraper" is Officially PLATINUM!