I voted 120-140 minutes. I just think it's a good length. Because LWW was 135 minutes and PC was 150 minutes, this would be best keeping in time with the other movies.
The Lord of the Rings is longer and more complicated, so it required a longer movie. (FOTR is 178 minutes.) Especially when you consider the size of VDT compared to FOTR, I would rather VDT not be dragged out to the same time length.

However, I wonder if they made it a shorter movie, it would attract more audiences. Not many people have the patience/attention span/physical capacity to sit in a theatre for 2.5 hours.

maybe, but it depends on the audience. take LOTR for example: the movies won tons of awards and tons of people liked them and went to see them - and they were 3-4 hours each! so it will depend, I think, on two things:

1: how well VotDT is made

2: if there is enough good material (like LOTR) to last for 2 or more hours

just my two cents.....

I have a gut feeling that the movie will go a little over two hours. I do hope so too!

I voted for more than 2hr and 20 min. I want as much Narnia as I can get!

Lots of popular movie series have films of 2 and a half hrs. LoTR, PoTC, and Narnia all had films longer than that. Dark Knight is around that range, too. Many small children sat through LWW and PC, so I wouldn't mind another film in that time frame, as long as it is time well spent. PC was not time well spent, becuase about half that near-3-hours is the same people beating each other up, which has a tendency to get slightly redundant after 45 minutes.

when I saw LWW for the first time, I was only 12 years old and at the time it was the longest and most violent movie I'd seen. I was glued. so I don't see what would be wrong with a long running time for VotDT - of it is over 2 hours!

I think VDT will be about the same as Prince Caspian, around 2 and a half hours.