I will give a resounding NO to that. If someone wanted to mod that then they can.. but I really don't think it has any place in TES and personally I think that it would burn me out on the combat. Just like when you play the zombie modes in call of duty.. too many enemies and after a while you just want it to end. Not a fan of that sort of gameplay myself. I want the combat to be interesting and stay interesting, if that means limiting it then so be it. Also, TES is not all about combat. TES has been about story and role playing since the dawn of it's existence.
Edit: BTW it frustrates me how everyone calls it horde mode like GOW was the first to ever implement enemy wave survival.. It's like people who think that Halo invented tea bagging when I have done it since the first Rainbow Six. Or how everyone compares every rpg to WoW.. That sort of thing just makes me grumble in my angry corner.
I agree about the term horde mode, imo it should be more justly called Survival Mode.
Here's how I would implement an ideal Skyrim Survival Mode:
Add in a new dungeon, an ancient Dragon Shrine Ruin that is currently being escavated. Curious, you walk in and talk to the foreman in charge of the operation, who tells you that they can't send a team in because the deeper they go, the more undead start to rise and pour out of the the first floor's catacombs.
The foreman will only take you seriously if you've risen to the head of a faction, if so he'll propose a deal with you: hold off the rising undead for as long as possible, and he'll split the artifacts and loot the team escavated with you.
Waves of undead start to come out as the escavation team treads deeper and deeper into the ruins below - a defense mechanism meant to block off the intruder's escape with a mass of undead. As you hold the line, the team is allowed to go further, and the deeper they tread, the more the artifacts and loot rise in value and interest.
If you die, obviously you have to reload whatever save you had last. If you feel like you can't handle another wave, hit the switch to signal the escavation team to stop, and to return. Once that happens, the foreman gives you your share of the loot.
You're allowed to bring anyone you wish, from faction companions, to hired mercenaries, to a pet dog.
That's how I envision my survival mode mod at the moment. As for the more interesting rewards, I'm thinking some spell tomes (with customly scripted spells of course), artifacts in the style of wabbajack and the staff of worms, and perhaps even a new dragon shout.