Perhaps they will do one handed and two handed staves ([censored] you dictionary, staves is a word), the difference being lesser and greater abilities. Lesser abilities might be a low level paralyze (although, of course, it could be used for some nasty work), and a higher level ability might be a strong lightning spell.
Sounds about right?
I've been curious about this - I'm afraid we may have the RPG staves of Oblivion back. The other option would be to be able to cast an equipped spell through your staff, amplifying it or adding additional effects.
Well, currently, there isn't any reason that we couldn't have both magical staves (unfit for close combat due to their magical nature) and regular melee staves, although I somehow doubt that.
Hopefully we get cast-on-use back for enchantment, but if they keep staves like they were in Oblivion, I'm not so sure...