Making her return to the Summertime Ball for the second year in a row is J-J-Jessie J! This image appears in the gallery:Summertime Ball 2012 Line-Up In Pictures 4. Making her return to the Summertime Ball for the second year in a row is J-J-Jessie J! Pic: PA Photos 15 images See the full gallery: Summertime Ball 2012 Line-Up In Pictures