There's good and there's bad with any change.
Some things I liked about classic more then the current game.
And others is the reverse.

I hope Cataclysm leaves a ton of good options as far as leveling goes.

One of the changes which began to kill EQ for me, was taking low level (mid level whatever) instances, and making them challenging for end level toons, without giving anything back for the lowbies.
Cazic Thule and Mistmoore as end-game 6-man's, and just having less options leveling up sucked.