Digital Blending or Exposure blending is a simple photoshop technique that is becoming increasingly popular now days. This technique allows the photographer to exposure correctly for the shadows, mid-tones and highlights within the scene, without the use of ND filters or any HDR Softwares.
There are many techniques used by different photographer and for mine you can see how i did the one above. As you can see from below, Layer 1, Layer 2, Layer 3 and Background represent the different exposures i used. This is then followed by Nik Color Efex Pro.