Seems like you've been getting some good details there. But there's more then just those two videoes. Bild has an interview with Jade Raymond, and ubisoft's pages feature an interview with Patrice Desilets. Also check this interview out:
It seems that Desmond will be resqued/escape, and that he is entering another animus to help his assassin friends.
Also if you go to gameinformers home page you'll find a reference to an interview with the person who is guiding ubisoft on the historical details. If you google her name you'll find the interview with her as well.
PS: Be sure to head over to my blog. There are some interesting remarks on the three concept art images (plus they are in high quality), and also a key for opening something extra on the ubisoft official assassins's creed II site.
(PS: send me a mail if you find something new.)