Permit a hit-and-run post here, but Cosma Shalizi has written one of the best broadsides against intelligent design I've ever seen: "The thing is, this leads to bad science, and, if an unbeliever can say so, bad religion. The stakes are more serious here than with silly 'devotionals with mathematical content,' but the issues are not that different. Doing what you must know is shoddy science, in the hope that it will provide cover for propagating the gospel, shows a poor opinion of your fellow creatures, of the gospel, and of God. Of your fellow creatures, because you are resorting to trickery, rather than honest persuasion or the example of your own life, to win converts. Of the gospel, because you do not trust its ability to change lives and win souls. Last and worst, of God, because you are perverting what you believe to be the divine gift of intelligence, and refusing to learn about the Creator from the creation. And for what? To protect your opinion about what measure you think it fitting for God to employ."
Nicely put. For more on the subject, see this post from ThomH.