StraightandNarrow, the issue is not that God grieves but that he is limited and finite (as Kushner believes). Kushner believes God grieves because he can't do anything about bad things.
In a book of essays edited by New Agers that I've been reading (in preparation for a lecture I'm giving and for my newsletter), _For the Love of God: Handbook for the Spirit_, eds. Richard Carlson and Benjamin Shield, there are essays by New Agers, Buddhists, Mind Science believers, assorted others, and avowed Christians (the Christians in this book say some of the same things the New Agers say). There is an essay by Kushner in which he states that he found an answer to the suffering in the world by reading Archibald MacLeish's modern version of Job, J.B. which revealed to Kushner that we should forgive God for "the world's messiness and imperfection," and that "God is not responsible for everything, but that some things in the world are beyond His power" (these are MacLeish's words which Kushner is quoting but he is agreeing with them) (p. 127).
Kushner does say that God does not send sickness and death, but his view is that God is not in charge and has limited say in what happens on earth. This is how Kushner has decided to explain suffering. Keep in mind, Campolo said we should consider Kushner's view of God as though this is a good thing to do.