Is the explaination any more than just "intelligence did it"?
Actually ID isn't even that bold. They won't say (except by hoping you'll assume it, i.e. fill in the blanks yourself without committing the IDer to anything) that intelligence actually did something, because they won't address how (or when or where or by whom or by what) instances of "intelligent design" are or were instantiated.
All they'll do is infer (or pretend to infer) the existence of "intelligent design" as an end product. All else is mystery, and I believe is intentionally kept so. Once you begin to talk about how design actually happens then you've got "creationism," which is harder to "wedge" with!
Also, when you move beyond the vacuousness of ID you've got schisms among antievolutionists because they can't agree on even the most general scenarios of earth and life history (age of the earth, flood and geology, progressive vs special creation, etc, etc) and they can't settle those disputes in a normal scientific manner because there are always significant elements of dogma in play.
Is the explanation any more than just "evolution" did it"? Substitute your favorite word. A theory is just a general way of interpreting the evidence on a regular basis. The presence of organized matter and physical laws to governing it in predictable fashion can be explained by an almighty intelligence. It may be beyond proof, but then that's not what science is all about, is it?