George R.R. Martin!
Ever since last year when I stumbled across the preview for Game of Thrones on Hulu while looking for something to watch, I have been hooked on the characters of the seven kingdoms. While I haven't read any of his other books besides the Song of Ice and Fire series, I can still say that he is one of the best writers I have ever read at creating characters (dozens of them) and maintaining all of their individual personalities flawlessly throughout thousands of pages. There is a reason he is hailed as the American Tolkien.
But honestly, if I have to give true credit to where my writing style and overall influences come from, my favorite writer has to be named as Stephen King. He is, and will forever be, the master. I hope one day I can meet him, and show him one of my books.