Dull screen?

Well the AMOLED screen on the GNex is very vivid, and the blacks are much deeper. Also compare brightness settings, as that can serve to enhance the difference.

 

AMOLED has extremely high contrast (good) with extremely inaccurate color (bad). Some are distracted by the inaccuracies, some don't mind (me). Right after playing with my wife's ET4G (Super Amoled PLus) , my LTEvo's super LCD screen also looks a little washed out. Even though the screen on the LTEvo is a generation newer and almost universally considered superior to the ET4G's. As mentioned, the screen brightness can also have an effect. The N7's default auto brightness is very low unless in bright direct sunlight. If you haven't done so, try turning auto off and setting the brightness to 60% or higher. I haven't noticed any extreme hit on battery life.