The Keep by Jennifer Egan. Really well done; a bit of a literary Rubick’s cube, with all that that implies. Recommended. (excerpt)
Guardian by Joe Haldeman. Read it in one sitting in the bath — back problems; don’t ask — and it promptly fell apart. Engaging enough but inbred, in a U.S./SF of-a-certain-generation way, and the final section smacks of wish-fulfillment.
Fairyland by Paul J. McAuley. A weird and wild ride. Dystopic near-future takes a sharp turn off the map. Recommended.