Great. Tech trading was always one of the most abused aspects of the game. Not being able to rely on dealing for techs makes the decision of how to tech through the tree very, very different and much, much more interesting. People will cry because it takes away a huge crutch, but it's a great change for the gameplay experience.
Another good change. With a reach of 3 hexes in any direction plus the increased importance of tactical terrain/unit movement (because of 1 unit per hex), city placement gets much more interesting.
This is the most exciting news, for me. Sounds awesome. Having more ways to customize your Civ and access unique strategic/playstyle opportunities is always good.
Exactly. There is a great deal of whining and gnashing of teeth over change because people will have to adapt their strategies. This is a good thing. I want a new game instead of Civ 4.5
People just want to do what they've always done. Don't fear change.