We're a little late to this party, what with the video being posted in 2010 and all, and with GizMag even writing it up, but it's still cool.  Check out the video, and the points the presenter makes.  Better yet, swing by the Sikorsky site to read more about it:

190 hp, high efficiency and power density electric motor

Weighing only 180 lbs with controller, the electric motor was designed to mimic power profiles of the legacy motor to minimize integration time and complexity.

· Safe and efficient high density energy storage system

Two battery packs, each containing a series of 45 Amp-hr lithium-ion cells comprise the energy storage system. For the Firefly™ application, Gaia provided a new chemistry battery cell, combining the best of their High Power and High Energy battery chemistries to meet the required energy demands.

· Automated monitoring and alert technologies

Sensors embedded within the mechanical, electrical and energy storage components provide real-time health data. Relevant results of this system are presented to the pilot real time in a standard symbology format.

· Advanced flight control system

Driven by the embedded sensor network, the mode-based flight control system features automated operation sequences and safeguard functionalities which monitor current aircraft conditions to ensure safe operating limitations are maintained throughout the flight.

But what's really interesting is the pitch they give for electric drive:

All-electric propulsion offers substantial benefits for current and future rotorcraft designs. With Firefly™, the development team has demonstrated a propulsion efficiency increase of roughly 300% from baseline.

In addition, electric motor technology is progressing in a direction that may, in the near future, negate the need for traditional rotorcraft drive components. This simplification not only reduces the number of moving parts, but directly results in significant noise reduction, reduced vibrations, and game changing advances in reliability with associated dramatic decreases in direct operating costs.

Efficiency?  Simplicity?  Noise and vibration reductions?  They're preaching to the choir.  However with a 15 minute flight time, it brings "Range Anxiety" into a completely new light.

We had hoped that by now there might be some clips of the bird in flight, but so far we haven't been able to find anything. Here's the video from AVweb that got us going on this in the first place: