(http://media1.gameinformer.com/imagefeed/featured/valve/secret/logo610.jpg)
Last October, shortly after the release of DotA v6.63, IceFrog announced that he would be leading a team at Valve Corporation as a lead developer, which came after the company contacted him and offered to show him their studio in Bellevue, Washington. Interest in such a project was amplified by Riot Games' League of Legends and S2 Games' Heroes of Newerth, leading many to show interest in a first-party adaptation on another platform by the current developer. After a year of interest, (along with some discontent Riot Games), Valve has officially announced their new project that IceFrog has been leading- Dota 2.
This title is one of three projects that Valve will have announced within the next eleven months. It is unknown when the testing phase may begin, but indications point to a much sooner phase than what a Blizzard Entertainment title may receive, judging by Valve's difference in process. DotA 2 has an approximate 2011 release date.
Dota 2 Gamescom Trailer (http://www.youtube.com/watch?v=-cSFPIwMEq4#ws)
Can't wait :D