Boy, I didn't either. Wow. And to think! All these years I've had the wrong idea about roleplaying! I'm so embarrassed! Thank you, thank you, msxyz, for setting us straight with incontrovertible "facts" about roleplaying! How ever can we repay you for your infinite wisdom in this matter?
Sort of...

It's possible Skyrim isn't an RPG if you look at strict definitions - I don't know that. But since many, many of us obivously RP when we play Skyrim (or other TES games), it's also obvious possible to RP when playing it.

To me, to RP is to create a character and create a story for that character within the framework the game provides. The anology with the writer is very accurate, I think. I "write" the story, but in actions (well, and screenshots) instead of words (ok, I use words as well, to explain the screenshots, and a couple of my characters have kept journals, but not as in actual fictional writing).