I realize that Speed is the governing attribute of your character's movement velocity, but I believe Athletics did also affect your movement speed (could be wrong here). Further, I'm concerned about the "sprint" functionality they have added. While I love the idea, it makes me again wonder if character speed is more "locked" or static than it was in the past Elder Scrolls games. In Morrowind and Oblivion, one of the first things I'd do is create a "sprint" spell that boosts my speed as much as possible for as long as possible as my character could has at that point in his development.
Personally, I greatly hope this is not the case. I loved Fallout 3 and New Vegas, but the fact that your character was so dang slow ensured that I never traveled long distances, instead utilizing fast-travel whenever possible. In the Elder Scrolls series, I love to play a blazingly fast Thief/Ranger class character, who uses minimal armor to keep the movement speed up. Further, I'd love to not resort to fast travel all the time, and Speed will play a large role in that.
There's a solid chance I'm over-reacting, and an even greater chance that this has already been addressed. But, I wanted to throw the topic out there and see if anyone has some better insights into the situation than I.