I love Minecraft! Once I heard that they might be adding horses, I couldn't wait! I built a big barn with a hay loft, many stalls, and tack room, and brick roof. I made a big pasture, a small one, a jumping ring, and a sheep pasture. The pastures have lots of tall grass and covered water troughs. I still have to build a farmhouse, cow pasture, chicken coop, and I have to grow lots more hay for more bales.
Luckily, I started next to a very large herd of horses. I've been taming a bunch of them. =)
And yes, all this on survival.
(I have to admit, I used cheats to get clay bricks, saddles, leads, and nametags. I justify this by telling myself it would take forever to find that many dungeons and lakes. XD)