It is affectionately referred to by the troops as R2-D2.

From a released statement
The complete C-RAM system networks a ground-based version of Phalanx together with the Army's Lightweight Counter Mortar Radar (LCMR) and Q-36 Target Acquisition Radar (AN/TPQ-36 Firefinder Radar). Unlike the naval version, C-RAM does not fire solid tungsten penetrators. Instead, self-destructing explosive bullets are used, in order to reduce the risk of civilian and friendly casualties.
What the hell does that mean? I hear you ask.
It means this... The Phalanx by itself is designed as a shoot down missiles and airplanes. Its radar isn't capable of tracking anything as small or as fast as a mortar or artillery shell. HOWEVER, the LCMR is capable to track incoming artillery and give warning to nearby friendlies to get out of the way before the ground they walk upon starts blowing up. The Q-36 is able to, for lack of a better term, do math to predict not only the path of the artillery shell on the way down, but follow its trajectory back to where it came from. The last bit about bullets means that the bullets are "tracer rounds' that are fired glow red and at a range of 5000 yards (I believe) they burn off their incendiary and the bullet pops. Judging by the white flashes of the popping bullets, I assume they're made out of Magnesium
If Israel gets one of these, it can shoot down an incoming Hezbollah Mortar or a Katusha rocket going ballistic before they hit population centers.
However it's still under testing, it's being used by the US Military forward bases away from population centers to test the effectiveness against insurgent mortar attacks and confirming that the bullets do infact self destruct as desired without the C-RAM reigning down a wall of steel against a neighborhood. Also as of now R2-D2 carries only 9000 rounds of ammunition, while firing off about 200 rounds a second, meaning a total continual fire time of 45 seconds.
http://www.youtube.com/watch?v=94BRkbFbITY <--- R2-D2 in action. If you listen carefully near the end you will hear a long series of popping, which are the bullets exploding, with a large bang from a mortar charge, and then more popping, indicating a hit and mid air intercept.
Neat eh?