That was my experience too, until Ulduar. I was raiding in there the first week it was out and taking down those two giant fire guardians outside of furnace area was, dare I say, challenging. They applied a debuff that, as far as we could figure out, couldn't be cleansed unless you made it down to the water at the bottom of the ramp, so you had to do the next couple of pulls while the whole raid was taking damage from these debuffs.

A few weeks later we went in and that debuff had been taken out... I was very disappointed. It was so much fun trying to figure out a way to get down to those pools while not dying. It took really strategy and skill. Sure, it was a rude awakening for those people who had only ever raided Naxx, but that was what was so great about it.

On a similar note, I think that trash can make a place feel epic... I think that trash has a much bigger impact on the epic feel of the place than the bosses. The first time I ventured into Molten Core (as a lvl 70), I was struck by how awesome it was to see giant flaming monsters trudging around inside of a volcano. I really felt like I was heading deep into the Black Rock Mountain and the trash played a big part in setting the scene.

Not only the trash though... now-a-day you can just walk right up to the raid entrance and hop in. No need to get attuned or complete a giant questline. Look at Molten Core and Blackwing Lair... the amount of effort it takes to actually get to the entrance of either of these raids for the first time is immense. Granted that did limit the amount of people who would raid endgame, and that's not what Blizz wants to do right now, but come on, don't just stick the entrance to Icecrown right where everyone can get to it... make us work for it at least a little bit.

As a healer in Ulduar, I was not sad to see the hopping flame debuff go bye bye. Once the giants were killed, the challenge the debuff provided was largely in keeping the healers from tabbing it. It was very annoying but not especially hard to deal with.