My understanding of Christopher Tolkien's position, such as that understanding is, indicates that he's very protective of his father's legacy as his father's; he's very much a curator. I seem to remember seeing references in articles to him frothing over into coldly-offended fury at the suggestion that he could create or back the creation of actual new fiction set in Middle-Earth.

As for The City, I'm very very intrigued. The title feels like it could come across as too forgettable, but then again if the book is good it could end up iconic instead. And the blurb promises just the kind of epic fantasy I like when it's executed well.

Setting store by the book's details at online retailers is probably a waste of time at this early stage, as there can't possibly be a finished copy, but if amazon UK's guestimate of 700 pages is based on any info at all it sounds like the book might be quite chunky, a good deal longer than was DG's wont I believe. Two books is hardly any kind of trend, but I think John Gwynne's debut Malice is also supposed to be quite long. Maybe some UK publishers are starting to become open to very lengthy epic fantasy debuts again? [Such books did serve them well in the 90s, after all.]

Hopefully it gets a North American publisher soon.