Well, this is what I get for opening my big mouth! Tony Jones linked back to my blog post on Creatio Ex Nihilo on his blog, which led to some very constructive remarks by many of his commentators. I felt compelled to reply, and figured I'd cross-post what I wrote here. Tony has also posted my reply on his blog.
1. First of all, I should clarify that I do appreciate a lot about process theology. I think that it's emphasis on the divine immanence can be an important corrective to theology that overly accentuate the divine transcendence, and to that degree, it serves an important theological role that I in no way want to deny. It's also among the most fresh and creative approaches to theology to emerge from the 20th century and I appreciate it if for no other reason than simply that it's interesting.
2. My own position could probably be best described as "panentheistic" in the Moltmannian sense of the term, which, at least as I read him, depends on the idea which is rooted in Anselm's ontological argument that God's being does not depend on the contingency of the world, but that God chooses to enter into the contingency of creation as an act of divine self-emptying for the sake of creation. What this approach offers is a way of understanding divine immanence that does not rely on a necessary God/world connection as does the God of process theology. God is, as one commentator noted, both within creation and transcendent, and God's being is not in that sense reliant on creation, but God in love chooses to descend within creation, ultimately even unto death.
3. That said, I want to make clear that it's entirely possible that process theology has some compelling responses to this, and Scot offers some insights that are certainly worth considering. However, I have yet to find an argument that I've found compelling to convince me that process thought does not, by virtue of taking away crucial elements of the divine omnipotence, seriously vacate the notion of divine providence. If the universe is free to act either in accord with or against God's plan then it is possible that, contrary to God's desires or intentions, the universe could propel itself, not toward God's salvific purposes, but into a cosmic death spiral. Only if God's intentions for the universe are understood to be implied by divine transcendence, and unalterable in principle except by God, is the idea of soteriology in any cosmic sense possible. This does require, as J.J. suggests, an eschatological reference point for salvation, though I would disagree that this is either untenable or immoral.
4. Again, I make no claims to comprehensive knowledge of all of the arguments made by process theologians, but I have mostly been interested in the approach offered by Charles Hartshorne (if I had gone a different way at PTS, I might have done my dissertation on him!). As philosophical theologians with a process orientation go, I think he's fascinating, but again, as I read his interpretation of the subject, ultimately God is, quite explicitly not the Ground of Being or a transcendent entity, but simply the greatest possible being within the universe. Now, other process theologians may have taken a different tack, and attempted to preserve a greater degree of divine sovereignty, and maybe some of them have solved the problems that I've suggested, but no process thinker that I've read has quite overcome these problems to my satisfaction.
5. On a positive note, I think that one of the contributions of process theology has been in the theology of science, insofar as it has given theologians of science a way of understanding divine agency in a scientifically understood world in a new and interesting way, but in the end, I think the approach to divine agency in the material world is better described by the view of someone like Austin Farrer than by John Polkinghorne or Ian Barbour (both of whom I love, but both of whom I wish leaned less heavily on elements of process thought.