Whether ID is a science or not shouldn't depend on whether its presuppositions come from the bible, devotion to the FSM, or anything else. What matters is whether the people proposing it make testable assumptions and use other tried and true scientific methodologies. To the extent that ID fails muster on THOSE grounds, it still has to prove itself as a science.
Which it doesn't.
That said, evolution is, as far as I know, unfalsifiable.
You don't know far enough. Among many, many things that would falsify ToE, if fossils of later and more complex species were found that were older than fossils of earlier, less complex species, ToE would be disproved. If it were not the case that all life on earth was based on DNA. Even a flying invertebrate with 4 limbs would falsify ToE.
The persistent lack of transitional forms in the fossil record (an apparent falsification) is usually got round by pointing to putative transitional forms that are routinely debunked later.
You couldn't be more wrong. Every fossil that has ever been found is transititional, literally, millions of them. Just today I heard about a fossil of a primitive turtle with only half a shell, just discovered. This sort of thing happens all the time.
This has been especially true in studies of human evolution.
False again. There is, if anything, an embarssment of riches of pre-human proto-hominid fossils.
So the hope is always held out that the next dig will turn up the "smoking gun" transitional form.
It would be ignorant to look for a single transitional form, when all fossils are transitional. The last 50 years has turned up many new pre-hominid fossils.
And the continuing difficulty of defining a transitional form without vicious circularity is another serious obstacle to discussing the question.
This is gibberish.
So if falsifiability is the sine qua non of scientific theories, evolution has a serious challenge of its own.
No, it doesn't. Are you aware of the many predictions that ToE makes, everyone of which has been borne out? Just for starters, ToE predicted that the earth would be very old, more than 100 million years old. Sixty years later, this turned out to be correct. ToE predicted that there would be a mechanism that caused replication with modification, and a hundred years later it was discovered (DNA.) I could go on and on, and would be happy to, if you like.
That's not to say that ID and evolution are equally adequate. I don't know enough about either theory to comment on that. Evolution, even if not falsifiable, is to be preferred over rivals because it more adequately explains the data. And if so, it deserves the nod.
ID is either unfalsifiable or falsified. In some respects, it makes no predictions (because, of course, the intent of an unknowable but all-powerful designer could never be known.) It does make some predictions about evolution itself, which have been disproved. For example, Behe predicted that ToE could never explain the evolution of disease resistance. Since then, the evolutionary pathway has been found.