Well, there's been a bunch of tidbits and stuff that I haven't bothered posting, but I thought that this was big enough.
A gameplay video (and interview) from E3:
http://youtu.be/W2CzsJ4K_qo
Here's another, with much of the same content but a few differences also:
http://youtu.be/ic6dKnv3WdU
Also in that one you can see that they decided to implement horses after all.