Wake by Robert J Sawyer
Caitlin Decter is young, pretty, feisty, a matematics genius-and blind. Still, she can surf the net with the best of them, following its complex paths clearly in her mind. But Caitlin's brain long ago co-opted her primary visual cortex to help her navigate online. So when she receives an implant to restore her sight, instead of seeing reality, the landscape of the World Wide Web explodes into her consciousness, spreading out all around her in a riot of colors and shapes. While exploring this amazing realm, she discovers something-some other-lurking in the background. And it's getting more and more intelligent with each passing day. The first of a spellbinding future history trilogy that charts what will happen when the world's first first, and superior, artificial-intelligence is born in the web.