It's definitely Warlock heavy but I'm still seeing Priest and Hunter fairly often. Very little Rogue, Warrior, or Shaman (which I play a ton).
Blizzard will need to start cranking out sets to keep my interest. MTG runs 4 new sets per year and that's with a few decades of card base. Hearthstone is going to need a good pace for new sets b/c it's such a small card base to build on. When the new cards are available and decks get tweaked it will be the same old thing again pretty quickly. That will be even worse if lots of people have the dust/gold built up to immediately create and play all the new stuff.
The single player set up for new sets will be cool, though. It would be awesome to have a few of them released each year.
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