In the DoTA 2 will be included all heroes of DOTA-AllStars. Likewise with all the upgrade path, item and skill will remain in DoTA 2.
One that will distinguish DoTA 2 with previous versions seen on the Source engine used. Like the graphics upgrade, and also the voice chat.
DoTA 2 is scheduled to attend for PC and Mac in 2011. This game will be released in retail, with many new features.