Well, 'A Fire Upon the Deep' is quite popular. It offers a unique view of a universe with different levels of intelligence and how they interact. 'Gateway' has its fans as well. The idea of exploring an ancient alien space station full of secrets is very appealing. 'Rendezvous with Rama' is also popular. The discovery of the huge, seemingly empty alien spacecraft and the mystery surrounding it draw in many readers.
Well, 'Artemis' was quite popular. It had a lot of buzz because it was by Andy Weir, who had already made a name for himself with 'The Martian'. People were excited to see his take on a lunar - based story. It has an exciting plot that involves a lot of action and intrigue in a future moon colony.
'Wool' by Hugh Howey was quite popular too. It's set in a post - apocalyptic silo, and the mystery and the characters' struggles within that confined space were really engaging for readers. The story gradually unfolds, revealing more about the world outside the silo as it progresses, which kept readers hooked.
I'm not sure which ones are the most popular exactly, but 'Snow Crash' by Neal Stephenson is often highly regarded. It's set in a future where the world has been transformed by a new form of technology and virtual reality, and it has a really unique and engaging plot.
I'm not entirely sure which ones were the most popular, but 'Doomsday Book' was widely talked about. It had an interesting premise of time - traveling historians.
Another popular one could be 'The Uplift War'. It was part of a well - known series and had a lot of fans who were into the idea of the uplift concept, where lower species are 'uplifted' to sentience by higher ones. It had exciting battles and interesting alien species interactions.
Another popular one might be 'The Uplift War' by David Brin. It's part of a series and in 1989 it was attracting a lot of attention for its unique take on the evolution of intelligent species and the politics between them.
I think 'The Collapsing Empire' was quite popular. It got a lot of attention for its unique story and engaging characters.
Probably 'Snow Crash' is also popular. It was quite ahead of its time with its ideas about virtual worlds and the future of society. It combines cyberpunk elements with a really engaging story, which made it a hit among science fiction readers in 1999 and still remains popular today. The unique language and the fast - paced plot make it stand out in the list of 1999 science fiction books.
I'd say 'Foundation's Edge' is quite popular. Asimov was already a big name in science fiction, and this addition to the Foundation series was eagerly awaited. It expanded on the already rich universe he had created, with more political intrigue and scientific ideas.
Probably 'Brasyl' too. Its vivid descriptions of a future Brazil and the complex narrative structure attracted a lot of readers. It's not just about the science - fictional elements but also about the exploration of a rich and diverse culture within a futuristic setting, which made it stand out among other books in the list.