Defense of the Ancients (DOTA) was a custom map originally designed for Warcraft III and it’s expansions.  It became so wildly popular in worldwide tournaments that it has inspired other titles—such as League of Legends—that use its action RTS gameplay style.  Valve hired one of the DOTA’s designers (IceFrog) and together they began to develop a standalone game titled DOTA2.  At Gamescom, they unveiled the first trailer for DOTA2 and while it doesn’t show any actual gameplay, they are having the first public tournament at the convention with a $1 million prize pool on the line.  One thing is clear:  DOTA2 will have a huge impact on eSports.