You guys have your labels all wrong.
Nerds are the ones that are incompetent when it comes to socializing, but will grow up to make 10x as much money as you do and will be banging chicks left and right because he spent all of his time growing up in front of the computer doing things that are worthwhile (I.E. PROGRAMMING, WEB PAGE MANAGEMENT, in other words, not spending time with an unfruitful hobby such as fragging ass in CS or leveling their midget paladin in eq) and has money flying out of his ass.
Geeks are nerds that won't be successful. They spend all of their time playing DnD with their future-homosexual friend in the basement. They also have bad hair cuts, and have an air of loser goth-esque about them. Geeks usually go to jail in their 30s for sexual assault and end up turning gay because of big ol bubba.
Dorks are just your average person that is slightly annoying, slobbers when talking, has bad taste in clothing, and is usually either chronically obese or skinny.