bls at The Topmost Apple blog has a timely reminder that not all, or even most, progressive Anglicans derive their theology from the writings of the Rt. Rev. John Shelby Spong, retired Bishop of Newark.
The former Bishop of Monmouth, for example, had this to say about one of Spong's theses:
[Spong's] objections seem to be to God as a being independent of the universe who acts within the universe in a way closely analogous to the way in which ordinary agents act. The trouble is that, while this might describe the belief of some rationalist divines in the modern period, and while it might sound very like the language of a good many ordinary religious practitioners, it bears no relation at all to what any serious theologian, from Origen to Barth and beyond, actually says about God - or, arguably, to what the practice of believers actually implies, whatever the pictorial idioms employed.
Whatever their disagreements with Rowan Williams in his role as the Archbishop of Canterbury, many progressive Anglicans still revere him as a theologian.