An observation I made that doesn't really seem to fit anywhere.
The four sets of event clues are representative of the 4 classic elements.
Event 1 was the video projected on the fountain of The Bellagio in Vegas. Water.
Event 2 was the skywriting around the world. Air.
Event 3 was the projections on stone buildings around the world. Earth.
Event 4 was the video and fireworks show in Seattle. Fire.