Role Playing Games are defined by one thing:customization. You make a character, you build their stats and personality the way you would want them, and you roleplay as a character of your design. MW3, for instance, isn't a role playing game because A:you're playing as a fixed character with no lines, and B:the only choice is which gun to use. Skyrim is actually more of an RPG than some recent Bioware titles, like ME3 and DA2, because those games tie you down with a name and backstory. You're always Shepard, you're always Hawke, you're always following the same story. You can customize your character face, build, and choices, but the endings are ultimately the same. In Skyrim, you can find out that you're the Dragonborn, or you can drink 30 black briar meads, decapitate a guardsman, leave a cryptic message next to his corpse with iron daggers, and run for the hills to live as an outlaw. It's not just a choice of what your character would do in this situation, it's a choice also of which situation your character would choose to be caught up in.