9 named dungeons / temples, not counting other places that people could
mistake for one, or unnamed dungeons (?)

Hyrule Field is *at least* 5 times the size of the one in Ocarina of
Time, not counting all the other regions.   the video shown last year
of the field that Link was riding through, fighting on horseback
against the boss that kidnaped the kid, is about the size of Ocarina of
Time's Hyrule field.

Japanese test team that played all the way through, who did not
complete all side quests took 70 hours.

the a 'clean' play-through of Ocarina of Time, for those that go
straight through and know what they're doing, ~30 hours

I'm assuming a novice player like me might need over 100 hours to
finish Twilight Princess, and not even see and do everything.

game is significantly more difficult than Wind Waker,  and on par with
if not somewhat more difficult that Ocarina of Time and MM.

the time between dungeons are spaced far apart, making the game long.
with different things to do, between dungeons, not the same thing over
and over again.

the game is very plot driven, rewarding.  Princess Zelda is a 'tradgic
figure' in this game.  the Twilight King is a mystery.

you could waste many hours in the village near the start of the game.