Evolution is just a theory, but...
If you want to replace the theory of evolution, at least try to come up with another theory, preferably a better one. I would love to hear it.
Unfortunately, ID is not that better theory. It is not even a theory.
The idea that the parts of evolution theory which are not yet fully understood can be substituted by an all-powerful higher being who has created our world the way it is, is false. Even if we accept the existence of such a higher being, it only makes matters harder to explain. Where does a being capable of creating a universe out of thin air come from? Who created such a powerful entity? In other words, who or what made god?
If you fail to understand how the natural environment in which we live (with all of its endless variation and wonder) could have been formed over a period of billions of years by a very complicated process called evolution, how can you just accept the existence of a higher being capable of creating all that in a matter of days or years? Which is harder to explain, a very complicated reality, or a single, invisible and omnipotent being that is capable of single-handedly creating such a very complicated reality?
The higher being in ID is -literally- a deus ex machina, a device once used to tie up loose ends in the storyline of a stage play (nowadays we might call it 'a Hollywood ending'). It does not explain anything, it just makes the audience feel good.
I can see the attraction of a deus ex machina or Hollywood ending for the masses. It provides an easy way out, in stead of having to think about the difficult questions that a stage play or a film might pose. The same goes for ID: having to think about an explanation for everything around us, is a lot harder than saying 'god created it' and giving up on trying to explain who or what that god is and where he came from.
I don't expect everyone to choose the harder path of trying to find real explanations, but for scientists who accept ID as a serious theory, I have no respect. ID is not a theory, it is a belief, which in terms of science means a cop-out. "I will never be able to understand this, so I just give up trying and assume there are higher powers at work."