That's a hard one. I'll decrease the playing time after a week or so, hopefully. Being released on a friday, this game will have me hooked all weekend. Won't be much in the way of sleep, I guess. It will be legendary!
I only work nights and despite being a badass, I'm still mainly lonely throughout the day. Skyrim shall fill that void! So probably around anywhere from 2-5 hours per session.
I didn't know that could happen.... and why would that stop you?
Well, months after Oblivion came out I was getting chunky. Not sure if it was related but by the time I got bored I was still a fat ass. I used to look in the mirror with my head tilted at a higher angle as to not emphasize my double chin. Good times.