One of the complaints many players had about Morrowind was the lack of any mounts in it, so in Oblivion, Bethesda added horses, but for all the hype surrounding them, I'd definately say that really weren't done that well, and assuming they will be in Skyrim as well, I hope Bethesda puts some work into improving them, because in Oblivion, I often just didn't bother with horses. By comparison, in games like Red Dead Redemption or Shadow of the Colossus. Of course, in the case of the former, horses were typically necessary rather than just helpful, considering many missions required using a horse, and I'd often find situations where I needed to chase or run from people on horseback, but regardless, my point is that if Bethesda wants horses to feel like a mechanic that is worth having rather than something that's just in the game to make the people complaining about their absence shut up, they'll need to do them better.
For one thing, I'd definately say that some form of mounted combat should be implemented. One of the reasons why I didn't like riding a horse that much in Oblivion was because I'd just have to dismount every five minutes to kill a wolf anyway, it's easier to just go on foot as I'm at least spared the dismounting for combat thing, and if I use sneak, I might even be able to avoid combat entirely. If there were some means of mounted combat, even if it were just with bows and spells, the player would at least have a way to kill weaker enemies without needing to dismount. And the thing with constantly dismounting to kill wolves might have been forgivable if you could actually outrun them on a horse, but in Oblivion, enemies seem to not know when to give up, and it seems that random animals will chase you halfway across Cyrodiil if they get the chance, and that's assuming you can outrun them at all, considering that horses aren't that fast, it seems like often, a character with a high enough speed and athletics skill can run just as fast on foot as on a horse. Going back to Red Dead Redemption, by comparison, even the slower horses seemed to be significantly faster than traveling on foot, and usually, I could outrun animals that tried to attack me if I was on horseback, so horses should certainly be faster, not much point in using them otherwise. And yes, the controls could do with improvement too, because they seemed rather awkward in Oblivion.
I never felt horses fit in the game. Skyrim is not earth so I'd like to see no earthly-creatures at all, like in Morrowind.
But Morrowind did have creatures from Earth... or have you never seen a rat before? Sure, they're bigger than rats tend to be in real life. And Bloodmoon also had bears and wolves, and regardless of whether you feel this was a good choice or not, I suspect that we can expect similar fauna in Skyrim to what we got in Bloodmoon, though obviously, Skyrim should have a lot more different types of creatures, being as it's a full standalone game and not just an expansion.
I used them mostly as a roleplaying element and they walked faster than my character (yes I walked. Everywhere. No fast travel. Just walking.)
They walked faster than your character? That seems hard to believe, because in my experience, the walking speed for horses seemed to generally be considerably slower than on foot. When following NPCs on horses while on foot, I actually often had to stop and wait for them to get further ahead so I didn't start running ahead of them, unless you mean running. In which case, yes, the running speed of horses does seem to have faster than it usually is on foot, but with most horses, I'd say the difference isn't enhough to make them worth using, for reasons other than role-playing. And I'd say if the only reason you'd use a horse, animals that people tended to ride because its faster, more convenient, and such, then something is wrong with their implementation.