I am still catching up with newer authors since I haven't been reading much fiction lately, until I got an ereader that is. That said...
For science fiction, I would recommend Iain M. Banks. Some of his stuff is in a series called the Culture series, which you could read in order though it isn't necessary to do so. Two of my favorites in that series are "Look to Windward" and "Use of Weapons". This is far-future "space opera" in a society where technology has progressed to the point where almost anything is possible, and some of the big players are artificial intelligences called "Minds". The stories are totally character-driven, with lots of drama and twists.
Another author I like is Neal Stephenson. "The Diamond Age" is really good. I have recently started reading the Baroque Cycle series. I would say this is a must for anyone who considers themself a liberal science nerd and wants to understand his or her own history. It tells the story of the birth of modern science and modern liberal democracy in the form of a wide-ranging adventure story with lots of colorful figures.
One of the "new guys" I have read recently is China Mieville, the New Corbuzon series. This is very dark and dramatic quasi-steampunk fantasy where you never know what will happen next.
I should also mention William Gibson though I am sure you would be up with him.