Being a shameless platonist, for me the answer is obvious. We only need mathematics since it is the only way to be able to reach certain things transcending ourselves - just as music or poetry is the only way to be able to reach certain other things (or maybe other aspects of the same things). Computers certainly may enhance our ability to reach these things and maybe even at some point will serve as a direct communication medium with them, but I don't see any sense in which the computers could replace either one or other side of that communication.
After a while - highly pleased to see tense controversy around this: +7-5 :D
Still later - now it is +13-7, spectacular!