I hope Civ4 isn't easier. Civ III and its expansion packs seem to have gotten progressively harder and players have kept up with it. I don't see why they would need to make it easier now. If make easier difficulty levels, I wouldn't care, but not a completely easier game.
If they do eliminate pollution, corruption, waste, and civil disorders, they are going to have to make an absolutely killer AI to make up for it in terms of difficulty. Keeping your citizens happy is a major part of the difficulty of the game. Corruption might make little difference since it would help the AI, but it would make it difficult to have governments the way they are implemented in Civ III. Pollution isn't that important, it'd merely affect the tediousness of the late game cleaning up of workers and the effects of Hydro plants would have to be changed.