Rock n' Roll royalty came out for the annual KIIS-FM Wango Tango concert in L.A. Saturday night. RadarOnline.com was there for all the action - from the star-packed Red Carpet to backstage.
Ludacris stopped by and told us he thinks Justin "is a young, cool kid."
Adam Lambert showed off his rhinestones - on his face - and Kelly Rowland told us what music she was rockin' to.
Last year's breakout star, Jason Derulo, sang his new hit single for us and told us he couldn't wait to see Ke$ha perform.
Sexy stars from MTV's The Hills Audrina Patridge and Ryan Cabrera shared music secrets with us but all the star power dimmed when 16 year old Justin Bieber walked the R/C.
Hot off his new single "Baby", the singing phenomenon even had radio host Ryan Seacrest in awe!