The Ecobee's street price seems to be about $400. At least, it was that price when this review was written a year ago: http://stevejenkins.com/blog/2010/11/product-review-ecobee-smart-thermostat/

I just bought a gen2 Nest. Only took a few minutes to install and get it online with my iPhone. I love it.

I can adjust the temp from anywhere now and it has sensors that will notice if nobody is home. I don't know how long it will take to earn back the $250 I spent but I know someday it will and it is SUPER SUPER COOL.

I use a Honeywell FocusPRO 6000 thermostat. It communicates with a 18 seer two-stage KeepRite air conditioner and a two-stage 96% AFUE KeepRite furnace. Installed by an industrial HVAC installer that installs systems at hospitals, factories, universities etc (not a typical home installer).

Cream of the crop. I talked to a HVAC guy at a wedding recently and he almost splooged in his pants when I described our heating and cooling system.

The understanding I got from the guy that installed my system is that you don't want your system to short cycle or have large swings in temperature programmed from one period to the next. People with digital thermostats like to alter their temperatures a bit too much. He told me just to set it and leave it alone. Furnace and air conditioner will automatically switch over. Ideally with a system like mine to get maximum efficiency from the air conditoner you actually want it to run pretty much all day in the lower stage. It will kick on to stage-two to "catch up" briefly but that doesn't last long. Constantly altering the temperatures can hurt more than help. In this case would cause the air conditioner to run at the higher stage more than it needs to.

Hey Chris-
I was looking at those the other day at Home Despot. I meant to go to the website for more information, but forgot to.

Are the lights blue? If so, I should buy one!

Hi Mark,
I really stressed over buying this thing. $250! But that remorse melted away immediately upon unboxing it.

You could do really mean things to your family with one of those and an iPhone.

The thermostat isn't the area that saves you money. It's bottlenecked by the quality of your heating and cooling system, the quality of its installation, and the homes build quality. A quality thermostat is the final piece that should be examined.

Ken,
I can't wait to turn the heat down while my wife is home and I am out.

I remember reading articles when the Nest first came out. I appeals to me and I like how if you have more than one zone (upstairs and downstairs zones) that it will eventually learn the best way to maximize the effeciency of heat between the two areas.

That being said, my contractor put way too many zones in the house for this to work with my in floor heating system. I could pick and choose zones I suppose but it would still prove expensive as just having one would not make any sense.