I've seen Greg a few times, and the only fan-boy con moment I had was lying to convention staff to connive my way into a Greg Bear "coffee klatch." Got to sit down at a table with him and about 10 other fans. Blood music was the bomb, but it totally lost me near the end -- the whole concept of reality being modified based on how many sentient beings perceive that reality? But everything before that gave me a science nippy hard-on. I also read DARWIN'S RADIO and thought that was the good cheese, and THE FORGE OF GOD which I wasn't that crazy about. However, it's seeing him speak to an audience that had the biggest impact on me. His "pessimistic reality" was like a major connection to my 20-something aspiring writer self.
So, Greg Bear, major influence. He is made of the good cheese.