Time to be on the alert again. Relmstein's got an informative post on his blog detailing the main differences between regular and heroic dungeons and why these heroic instances in the World of Warcraft's Burning Crusade expansion aren't as great as they were supposed to be previously.

His post noted how the loot tables didn't seem to change from regular to heroic mode across certain instances. In terms of risk against reward, you're entailing more risk without any seemingly noticeable upgrade to the award you're supposed to get from the heroic version of the instance you're playing in.

Worse still, it seems the only real payoff shows itself with the assurance of an epic item from the final bosses of each affected heroic instance. Even then, there's no assurance that anyone in your group can actually use the said items.

Bottom line: If you're thinking of trying Blizzard's uber-difficult heroic mode, do it to master your skill, but don't always expect it to turn out as great as you'd hope it would be. As for the affected instances, be careful when visiting the Black Morass, Shadow Labs, Mechanar, Botanica, and Arcatraz instances under heroic mode.