I have heard that you can't use magic from the horse. IS THIS TRUE?!

Yep.

Yes. The animations would look awkward.

and a mod already fixes it

Eh? How? I can picture it in my head easily. Master spells might be a tad unusual, but it's not difficult to raise a hand to charge the spell and then release. Dual-casting would be out, but that's no biggie.

Edit: Now that I think about, dual-casting would be fine, too. I can't imagine why they haven't implemented this yet :/

Speaking of dual cast, can you dual wield melee weapons?

On topic, magic should be castable from horseback, even if it's just from a staff.

as if the controls on horseback didnt svck enough, you also cant use magic.dont know why its not like you would become to powerfull if you could fire a few fireballs from horseback.

Bethesda is really weird... the developers are great when it comes to Open World Games, they promote "Freedom", but they always miss the small things like these >.>

maybe because only a few weeks ago they implemented fighting on horse back to start with.

But why implement it half-way at all?