JOHN C. WRIGHT, CRAVEN CAPITALIST: More Googling revealed this review/interview. If you read The Golden Age and found it really jarring that it just ended in the middle of everything--well, here's your answer:

The whole manuscript was composed, written and sold as one unbroken story; the publisher estimated (and I think, wisely) that more people would buy two $25 dollar hardcovers from an unknown author than would buy one telephone-book- sized $40 or $50 dollar book.

Likewise, after the first volume was published, it had received more favorable reviews than are common for a novice author, and the publisher calculated that he and I could double our revenues if we divided the second volume. My children, my beloved wife, and my patient creditors can certainly use the money.

My only regret is that this decision came after the first volume was printed: so that warning I put at the end of volume one (over my editor's objection) that the story was to be concluded in the next volume, now turns out to be false; it will be continued, not concluded. I do not mind rising the price to my readers, if it turns out that I underestimated the market value of my craft; but I do mind misleading the readers, and I hope not to loose their goodwill: I need their money more than they need my books.

It's weird: SF authors write trilogies for commercial reasons (outlined above) but usually they know they're writing trilogies--so the individual books are written to be self-contained. Wright's trilogy clearly isn't; the divisions between books are the natural divisions of the story but it's all the same story; this isn't like when Nancy Kress reshuffles characters in her trilogies (Beggars and Probability) and you end up with separate novels. Even though you end up reading the whole trilogy anyway so you can see how far the story goes. So, I mean, it's like Wright's work is being both more and less compromised by economic concerns: more because in order to sell more books his one book gets split into three, and less because--hey--he didn't have to change anything and write three separate novels and have to explain what had gone before and everything. You have to admire a guy just coming out and saying, "I'm selling it this way because I can make more money this way, so if you like what I write, please buy the whole thing. If I destroy my marketplace value by coming off like a complete capitalist ass who's taking advantage of my readers, well then, so be it, Jedi." Because it's not like he's doing anything different from any other trilogy-writer. He's just being pretty up-front about it.

But anyway, if you're going to read Wright, go in knowing you have to read the whole thing. Hopefully marketplace pressures will reverse themselves and we'll get a giant collected edition one of these days. In fact, that would be an additional book for people to buy, so it'll probably be out sooner rather than later.