Honestly, I don't remember any heroics (BC or Wrath) being as hard as Cata heroics, but that could be for any number of reasons. I have no issues with Cataclysm heroic's difficulty level.
It is possible, or even likely, that the random dungeon finder makes cata heroics seem harder, because people, more often than not, get stuck with idiots who don't know what they're doing. Whereas in the Burning Crusades and Wrath, I did heroics almost exclusively with people I knew, or people from within my guild; that right there is probably giving me the false impression that non-cata heroics were easier at release. Now i queue solo for a lot of stuff, so I'm getting exposed to a lot of bad players.
But with the way Blizzard talks, it does appear that they purposely were trying to make heroics more challenging in Cataclysm. It makes sense that they would try and step up the difficulty level in Cataclysm; how long have we been playing this game? We should be better by now! Any non-casual wow player that has been around since at least Wrath, should have improved their game-play somewhat. So cata heroics could seem easier since people have stepped up their game; harder, because maybe they are harder; or both, given people's luck using the random dungeon finder.
This post proves absolutely nothing and should be deleted :lol