Nobel Prize for Medicine/Physiology

As you have probably heard already, Andrew Fire and Craig Mello have won the Nobel Prize in Medicine for the discovery of RNA interference.
Jake Young explains what RNAi are and what they do and why is this so revolutionary. Then he explains why those two people got the Nobel for this work instead of some others.
Alex Palazzo (also here), Abel PharmBoy, Carl Zimmer, Nick Anthis and PZ Myers have more and explain it much better than I could ever do. The last time the Nobel was given for work I really understand and like was in 1973 – ah, the good old days when the Nobel did not require molecular biology!
Anyway, this is the first time a Nobel was given for something that was discovered at the time when I was already in the lab and I remember the rumors about it around the molecular labs in the Department. Usually it takes decades for the finding to get a Nobel (and in my field, all the “founders” are dead by now), so this was really fast – indicating how important it is.