My favourite biome is not listed here. As it is not a vanilla minecraft biome. I have played a few highly custom maps with amazing biomes. Perhaps some of you are familiar with the server, not sure. Glowcanoes: huge round areas laid out like a volcanoe, with walls reaching the 200 height, forested on the outside, with netherrack and glowstone filling the upper layer of the inside, but buried underneath starting around level 70 was carpeted with ores and watery lakes, with massivly tall netherbrick towers, and helish huge netherbrick fortresses underneath and lava lakes near bedrock level. Giant pumpkin plains, Giant mushroom forests, twisted obsidian 'worm' style formations, Waterfall sky islands. 'diamond' biomes. massive floating land masses with thick and frequent veins of diamond ore. Difficult to get to, and somewhat dangerous, but amazing. The list goes on. Also, you didn't list 'ocean' biome. Which a lot of people seem to love.
Savannah by far. I just really like the flat emptiness, with the trees and occasion hill. I've always wanted to see some of the landscapes like those in eastern Russia(seen it from plane though) and Africa.
Biomes you left out: - Hell - Ocean - River - Jungle - Ice plains - Sky (end) - Flower forest - Mushroom island - Snowy mountains/hills - Deep ocean - Swamp Anyway, my favourite is the forest. The grass texture isn't an eyesore unlike the desert and Mesa. Plenty of wood, water and recsources, flat land for building and the occasional mountain!
I love extreme hills Just getting on top of a mountain and peering over the landscape, and seeing the structures that Minecraft can generate in them. Then of course jumping off the mountain into a lake.