Mozart, Beethoven and Vivaldi are three of the great composers in history and the music they have written will stay in history forever. They were raw talents exposed to music from an early age, and with few distractions they had everything they needed to develop incredibly fast.
Talents of today don't get quite the same appreciation. Maybe someone has to die first, and then let some centuries pass..? One person I find absolutely incredible is Imogen Heap. Just look att this!