[citation][nom]ddpruitt[/nom]Semantics. What Blizzard calls an expansion is sold as a DLC for other games (BF, MW, SC2, etc) by companies aren't raping you (yet) for everything you have. Your paying near full price for a couple of levels and 6 extra characters, I buy new games cheaper than that. I betcha the same people complaining about SimCity, D3, and A:CM buy this and complain. Writings on the wall.edit: by SC2 I mean Supreme Commander not StarCraft, stupid mistake[/citation]
From the first few missions alone, I can see that HOTS definitely changes things up and adds enough content to be called an expansion, and is worth the price point. Personally, I'm pleasantly surprised that it is priced at $40, rather than the nowadays $60 standard for new games.
As one of the people who were deeply disappointed in the Diablo 3 debacle, I can say without a shadow of a doubt that Heart of the Swarm is not plagued by the same issues, and looks to be a thoroughly enjoyable experience.