Can agree with the Hyperion cantos by Dan Simmons.
Other good Sci-Fi series of note:
The Mars Trilogy by Kim Stanley Robinson. Written in the 90s, it's a mostly "hard science" vision of the colonisation of Mars. Some of the stuff is a bit dated, but still a good read.
The Dune series by Frank Herbert. Probably one of the most iconic Sci-Fi series ever written. Basically a must read (at least the first 3-4 books) for any fan. Haven't read the "new" books written by his son and Kevin J. Anderson, but they don't get good reviews.
The Commonwealth series by Peter F Hamilton. Fantastic setting, though I have a love-hate relationship with some of his characters. Skip the "prequel" Misspent Youth unless you're a competitionist, and the last two, The Chronicle of the Fallers is very low tech for a Sci-Fi story.
The Culture series by Ian M Banks. Just started it myself, but it comes highly recommended, and I've enjoyed it immensely so far.
If you're up for some classics, then Issac Asimov's Foundation series and Robot series are great, if you can get past the liberal use of "atomics". It's a lot of fun reading the old short stories in both series from the 50s and 60s, and then see how he merges them in his novels of the 80s.
If you like Star Wars, I can highly recommend many of the series from the 90s, most notably the Thrawn Trillogy and Kevin J. Anderson's Jedi stories.
Can't remember of any other Sci-Fi series that I've read off hand, but this should keep you occupied for a few months.
