I know that on certain sites i would get flamed for this, but my favourite player is Dave Mustaine. He isn't the most technical solo player (though i do love his solos - they're so damn aggressive!), but his rhythm is second to none. He is a genius riff writer, and he possesses true song writing skill. He's a legend. Don't worry, i'm not one of those Metallica hating Megadeth fans (i think both bands are legends), but the guy gets a lot of BS and hateful comments flung at him, and he doesn't care. I love everything about the guy's playing/style, and far from being overrated, he doesn't get a tenth of the respect he deserves.
I also can't help admiring Brian May. Nobody else on earth sounds like him, same with Ritchie Blackmore. Jimi Hendrix, Marty Friedman, Chris Broderick, Chris Poland, Michael Amott, Ritchie Sambora......i won't list all day long, but there are lot of favourite guitarists in my head.