2 hour nights? Seriously? And if so, why does Winter have an 8 hour day? Winter and Summer, being opposite angles of the world in relation to the sun, should be have the same lengths in reverse.
2 hour nights during the longest day of the year, yes. This is when the sky is *completely dark*. On each side of these two hours are 2 hours of twilight where you start getting light from the now lighting up atmosphere. http://www.youtube.com/watch?v=Xm_Cn8-DCNc, but this wouldn't be nice to the vampires, would it?
But even this far north, during the darkest day of the month, it would not be complete darkness all day. So no, the time isn't equal in reverse, and twilight also produce daylight long before the sun even shows up.
So if you count the twilight hours, you would have a 6 hour "night" between sunset and sunrise, of which only 2 hours will be really really dark. I gave this a test in Arma2 where I moved Takistan (has better modeled twilight than Chernarus) to Torshavn in the Faroe islands (approx lon W6.75° lat N62°). At July 1st, despite being south of the polar circle, I'm getting a decrease in scene brightness, but not enough to cause any problems playing in it. At midnight, it's still bright enough to fight without any night vision. The sky is still pretty bright but I'm able to make out about 10 stars. At January 1st, it will be in complete darkness from 6 in the evening to 6 in the morning, and *then* the twilight kicks in. At 5pm I can make out about 50-60 stars, easily identifying the big dipper, but objects on the ground are still hard to see. At 5am it's a little bit brighter with about 30-40 stars visible, ground objects also clearly visible. 3:15pm in winter is as bright as it is midnight in summer.
So to conclude, 12 hours in complete darkness during winter does not correspond equally to the 22 hours of almost complete brightness during the summer. Proven with a game that tries to model this fairly accurately, and without any "twists" added to it. However, 12 hours in complete darkness during winter (6pm-6am), 6 hours of daytime (9am-3pm), and 3 hours of twilight on either side, will not be welcomed well with the majority of players. Which is why I lengthened the day and stretched the twilight. Sunrises and sunsets in the game will be awesome, but the game speed prevents us from really enjoying it. Believe me, there is some thought to this that goes beyond my own personal preference.