It also redifined some of the exisiting RTS rules. Many would say that where we are right now is where RTS developers are going to stop. There are no more things to invent, or innovative ideas that will come along. All I can say is, you are far too misinformed. Look at how something as simple as adding the third dimension is adding to the gameplay of Empire Earth.
Units can now take cover behind walls to evade enemy fire.
It is adding more strategy to the whole strategy genre. A new blend of genres is breathing new life into the RTS world. Warcraft 3 for example, promises to deliver a mix of Roleplaying, and Strategy. In this case, you get the best of both worlds. Let's not forget the handful of titles that ventured out and mixed together First Person Shooters and Strategy.