Sunrise, Orange River
This photo was originally taken on 2010-01-07. I think it is visually compelling because:
* Clouds: the morning sky provided dramatic clouds
* Color: the sun lit the mountains with an orange glow
* Composition: the morning sky is the subject here, and it occupies 2/3 of the image. The orange mountains provide natural separation between the sky and the darker river. And, there are three items that provide symmetry in the foreground.
* Representation: as Tracy said, this photo represents Africa: in all its beauty, in all its barrenness (desert beyond the frame), and all its lushness (life-giving river in the foreground).