Why is Nest Such a Big Deal?

I keeping hearing about how Nest is so great, and it is the best thing since sliced bread, but I really do not get it.

I uses Alarm.com for all of my Home Automation and security in my house and it does way more than what Nest in regards to a "Smart Thermostat"

Read: http://www.cepro.com/article/alarmcom_cloud_service_may_yield_smartest_thermostat_on_the_planet/

Now I see MB has some new integration that allows you to control your thermostat from your car, but why. Alarm.com allows my phone automatically changes my thermostat to a specified temperature when I get within 5 miles of my house.

Now I must say the Nest thermostat is a beautiful piece of hardware, but in regards to functionality I simply don't see what makes it so special.