Heroes in SC2?

Well so i've heard b4 that blizard announced that heroes won't be in sc2, but that's probably just in the case for Mutliplayer and typical skirmish and so on. But of course they'd have to be playable and usable (like in sc1 ) during Campaign and Player created maps (although blizzard didn't show us raynor in action in blizzcon ) So i was thinking what unit they would now emerge as, and whether they would still attain their previous characteristic of simply using the model of typical unit counterparts, but varying in terms of Stats and stuff; except in the case for Kerrigan. (<- i actually kinda liked that idea)

This might've been already discussed, if so plz direct me to the appropriate thread, as I'm "relatively new"

 

Yep, it has.
http://www.starcraft2forum.org/forums/index.php?topic=77.0 Discussion about style of heroes (SC Original vs WarCraft 3).
http://www.starcraft2forum.org/forums/index.php?topic=555.0 Discussion about heroes in multiplayer.

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