I would like to personally thank NeutralCreeps again on this one.
Source: Blizzard DOTA joins Dota genre wars

Activision Blizzard, one of the world's most popular video game companies has announced via Blizzcon, their entry to the Dota genre.

For those who have no idea what the Dota genre is, Wikipedia answers:

The Dota genre is a sub-genre of Real-time strategy video games, characterized by role-playing elements.

Blizzard DOTA will be a Starcraft 2 mod officially endorsed by the developers behind Starcraft 2. It was announced that this will be FREE to those who already purchased Starcraft II: Wings of Liberty. As an official Blizzard map, this wouldn't be just another one of those run-of-the-mill Starcraft 2 DotA clones like Storm of the Imperial Sanctum.

Watch Matt Gotcher (SC2 developer) as he talks about Starcraft 2 DotA.
I really think we are seeing a huge influx of Dota genre games lately.

Other games in the Dota genre:
Dota 2 (Valve)
Heroes of Newerth (S2 Games)