Hi! I agree with Unicorn: Enya's music is not only beautiful, but it has very high level of musical and artistic quality. Her solo voice is one of the most beautiful female voice in popular music and she's the master of layered vocals. The melodies in her songs are breathtakingly perfect and her compositions can be very complex. She does all the instrumentation with different instruments (piano, cello, percussion instruments, etc.) and she can develop the most wonderful and most natural synthesizer samples. She tries to show us beauty, innocence and real values of our life through her music.
I love Orinoco Flow, but if you feel that you heard that song too many times I suggest to listen to her less known pieces. She has many songs that have different style. For example Water Shows The Hidden Heart is like an aria from an opera, Cursum Perficio is like a classical masterpiece, Aldebaran and Smaointe also have unique style, try Aniron from LOTR, it is breathtaking, try Journey Of The Angels from her new album, it is perfect, and I could continue.