Question #1: Let's say there was a seer who could tell you definitively whether or not you have the talent to be a published writer. Absolute 100% accuracy. But. If the seer person said no, that's that. Final answer. Would you want to know?
Question #2: If the seer person said no, you don't have the talent to be a published writer, would you still write?
#1: Jesus, yes I'd want to know! Do you know how much time and effort, and trees I could save right now if I knew the answer was no?
#2: Duh! Of course I would still write! I might stratch my head at the logic of entering an MFA at the moment, but I would keep writing.
I'd keep doing NaNoWriMo and like most of the other participants I would never in a million years expect anything more out of the experience than my entertainment and perhaps the entertainment of a few friends. My father plays guitar and those are roughly his expectations of his musical ability.
I would have to, of course, rethink my career. Teaching positions don't come to people who haven't been published as that outside stamp of approval is required by academia but perhaps I could run a writer's retreat. That could be fun.
Then agin, the comment I left on Nathan's blog was that if I would never be published that I'd like to know ASAP so that I could start working on my trophy-wife body. See, if I had to write merely for pleasure I'd need income. And maybe convincing some poor rich shmuck to provide for me while I spent his money could satisfy the part of my brain that, by nature, wants to create character and drama. Hmm... possibilities ... LOL!
Margosita also answered this question in her blog.