Correct. The Surface Pro 2 is very well designed (excellent cooling engineering applied), and the low power consumption of the CPU of this generation of processors, really allows this to be a possibility.
I know it might be hard to believe, as many are used to consumer grade laptops, where the market for those is: "What are the highest specs for the lowest price, I don't care about anything else", which results in noisy systems (and poor or not great build quality, and so on).
The fan will kick-in if you watch a lot of Flash videos (YouTube), for long period of time in a row, when you are plugged in, if you wonder. Basically anything that is GPU intensive, or CPU intensive for long period of time, will kick the fans. The fans are really quiet for their size, and despite 2 of them, unless they go at near full speed, you won't be really hearing them.
The device is expensive, but you see that Microsoft didn't cheap out anywhere (well.. if we ignore the webcam). Solid build quality, super fast components, high quality components, low voltage variation of all components, high quality cooling solution, very good cooling engineering, excellent overall product engineering, unique and very nice looking device (doesn't try to be a look-alike Apple product)