Grizzleheim is on the test servers on Tuesday, and expect it to roll out to the live game sometime in the near future.
Go check out the full article. You won't want to miss the screenshots over there as well. Three really good ones of the new races.
Keep in mind, no official announcement has come from Kingsisle to the fansites yet. When that happens, I'll forward it along. I just think KI wanted to give IGN the scoop. IGN has been a fantastic gaming newsite site 1998, so it was an extremely good choice.