There's a rumor floating around that the first legendary pokemon will spawn at Comic Con in San Diego at 2 PM, or in just TWO HOURS. Let's see if they're right!
Here's a counter showing how much time is left before the legendary spawns:
http://www.tickcounter.com/countdown/1469394000000/us-pacific/dhms/FFFFFF3B5998000000FF0000/LEGENDARY_POKEMON_@_32.7052395,_-117.168727