OK....having read all this thread (OK a lot of it skim read) I've decided to throw my hat into the ring....
The OP asked "What is really ID", and referenced age of Earth, when and how did designer create life, and observations for the answer.
I think all here on both sides would agree that ID is presented as the (supposedly) scientific alternative to the ToE in describing life on Earth. The intention of Philip Johnson et al was to introduce ID into the science classroom as a competing theory against the ToE.
Therefore, to be classed as science it MUST take the scientific approach and no other. If it abandons the scientific approach it can be taught in say religious studies classes - perhaps as a theological mechanism to explain creation......but it cannot be taught in a science class unless it follows scientific methodology.
So,
Let's remind ourselves what scientific methodology entails:
1) Observation of real-life data/events
2) Formulation of a theory that explains the observations.
3) Generations of predication that the theory would support
4) Generation of predications that cannot happen
5) Test the predications against the model, then reject, or tentatively accept dependent upon the real life data
6) Look for other forms of real-life data that support or falsify the model and refine accordingly.
OK then:
For ID to be accepted in science, these science threads, and (most important of all!) in school classrooms, the six categories above need to be adhered to.
1) Exactly what real life events do ID'ers want to use for their model?
2) What is the working model of ID? Is it only "God did it" or something more qualitative?
3) What predications can ID make in support of its central theory?
4) How can ID be falsified - what does it predict cannot happen?
5) How can the predictions be tested against the theory?
6) What supporting evidence from elsewhere can be used to refine the theory?
The ToE passes all these categories and has done so repeatedly for 150 years. It is up to the ID'ers to explicitly say now how each of these scientific investigative steps has been met and passed (with citations please).