#2 I don't have to buy a second power supply to carry around. My monitor is my power supply at my desk - saves $80.
#3 In the past it has been cheaper than other 27-30" monitors - saves $50.
$230 in savings is nothing to sneeze at…
#4 has a camera and speakers. This does not save me money but is convenient. It might save someone else money over buying a camera. It's HD to boot.
#5 it lets me pass through the thunderbolt capability and add thunderbolt accessories if they ever become available
#6 1Gb ethernet port for my macbook air
#7 power savings - even being the power brick for my laptop it seems to give off no heat. I t uses much less power than other LCD screens I've used in the past.