One thing I hate in most modern MMOs is that there is only one path to level up and any alts will be playing through the exact same content. Back in old EQ1 you could level up in many areas of the world, and even in WoW iirc you could level 2 characters to 40 in each faction and 1 character in each faction from 40 to 60 without repeating content other than dungeons.
I am really hoping that ESO will have multiple levelling paths to follow.