@Loreana;
I have to say that calling Naxx tough is stretching it a bit. For me, a raider from Sunwell in Sunwell gear, Naxx wasn't tough. There was no challenge there at all, at any point. Moving left-right on Thaddius? Not hard. Iceblocks on Sapp? Not hard. Void zones, dancing, plaguebombs, decimates, mind controlling the adds on Raz, Frogger, not hard. Heroics were the same; they weren't tough. Same with ToC; we did it with alts in PvP gear and blues.

But I don't think WotLK was necessarily too easy. I think their aim for the early content was to make easy content to ease a bigger percentage of the population of the game into raiding, and they certainly did that since we can now PuG raids. Where they lost my interest was not making challenging content at the earlier levels (Sarth 3d being a quasi-exception as that really wasn't hard either.) I think there should be content for all skill-levels at all stages and T7 missed that as there were no hard-modes, which I gather are challenging (although I have to say I've seen my boyfriend in PuG runs blast through some of the ICC hardmodes.) For this reason, they lost me early on. I hope to see something more engaging in the next expansion. :)