cool... but it might be a cheat trick...
I was searching for a video of an engineer that made straight water... he owns tha company that makes the water show in front of the bigest hotel in Las Vegas.
I'm suspecting this is a trick of the camera speed.
31 frames per second and precisely 31 drops per second perhaps?
The trick I feel could possibly be based on ultrasonics. The way the "droplets at the end of the video spead out and a change in back ground noise do make me suspect sound of some kind. Neat trick though.
Im thinking of superconductors. but it only works on metals..remember the floating metals?
that was pretty amazing regardeless on how it 's done...
One of the comments under the video sayd that it was done with a "strobe light"... 
I have to say that I think Ocalhoun has it correct. This looks like a 'stroboscopic' effect. It could be done, as ocalhoun suggests, by selecting a camera expose rate; alternatively you could use a strobe light to illuminate the drip-stream...
It is a strobe light behind the stream of water - I have seen it done at school. Any tap will do it and most school science departments have a strobe light - close the blinds, turn the tap on and start the strobe.
The effect of the drops slowing, rising etc. is achieved by changing the strobe rate.
David.