NPR is now polling to see what the top 100 Science Fiction and Fantasy novels are from it’s users. It’s a great little poll I have a few issues with but you should definitely check it out and vote.
I just bristle at the fact works of Fantasy and works of Science Fiction are almost always lumped together in these types of lists by reporters who have not read extensively in either genre. While I admit there are no less than a million ways these two genres can intermingled on the page, each genre is more than fully developed enough to justify keeping them separate. For me I always enjoyed reading Fantasy novels but it was always for the pure pleasure. It was the Science Fiction that I read which made me consider and question myself and the world around me.
Some authors (Philip K Dick for example) have such a depth and breadth of work I’m always hard put to vote for a single work to be recognized. And there’s always the ‘classics’, the obvious choices which I was tasked to read in school rather than discovering them on my own. So here’s my top ten list taken from the choices at NPR:
Neuromancer – Gibson
Man in the High Castle – Dick
Stainless Steel Rat (series) – Harrison (had to have one satiric entry on the list)
Dune – Herbert
Deathbird Stories – Ellison
20,000 Leagues Under the Sea – Verne
A Clockwork Orange – Burgess
Left Hand of Darkness – LeGuin
Fahrenheit 451 – Bradbury
Solaris – Lem
Actionsuit Alert! 
I largely agree with your list. I would also add Brave New World – best dystopian satire ever; I love F451, but Huxley’s novel is epic in ideas and scope. Handmaid’s Tale is awfully good as well, especially in the exploration of sexual politics in a theocratic dystopia.
Fun to think about. Makes me want to re-read about a dozen books!
I’ve never read Handmaid’s Tale so I’ll have to check that out. Brave New World deserves to be there, but I kept it out of my top ten because I first read it via assignment from school and didn’t really make a personal connection. I absolutely love Bradbury and had to have him on my list no matter what, and F451 is so simple and elegant like everything he does.