How quickly can you...
- Read all 25 words out loud: RED, GREEN, BLUE, ... (Try it now!)
- Say all 25 colors out loud: GREEN, YELLOW, WHITE... (Try it now!)
The example provided by the Google testing blog obfuscates the Stroop effect with the quite probably different reaction times needed for the tasks of 1) reading labels and 2) converting color samples to their color names.
Another demo of the Stroop effect from Wikipedia is presented here:
Say the color of these words as fast as you can:
Green Red Blue
Yellow Blue Yellow
Blue Yellow Red
Green Yellow Green
According to the Stroop effect, the first set of colors would have had a faster reaction time.
Here's my original SETI research