I made the mistake of reading the first half in 15 minute increments, then leaving it for a couple of months before reading the rest. Given that the story involves dozens (human and AI) characters, many of whom have secret agendas, this sporadic reading meant that I'm sure some reveals at the end went by totally unnoticed. Still, this seems like what I expected a novel in the Culture series to be like, particularly the ship Minds being protagonists. Not entirely satisfied with the ending, but totally worth the time.