Just to give a little idea, here's part one of the 2005 E3 OB demo http://www.youtube.com/watch?v=de1M4Q_g2eg There are six parts in total.

Obviously some parts were scripted for the E3 demo but there were some things I noticed that were different to the finished game:

Coloured reticle

Map

Voice actors

And the part where Todd said "there are over 200 hand crafted dungeons." I believe that's what they intended but found it was way too much work. Don't worry I'm sure the 150 dungeons in Skyrim will be hand crafted, they have a much bigger team now.