Well, it seems to be a common theme for people here to post "Why this update sux", and the like, so I thought I'd make a post as to why I think it's a fun addition to minecraft.
The biggest thing is, it makes me want to explore again, which is something I haven't felt since I first joined back in Alpha. Suddenly, I want to go spelunking again, and look for abandoned mineshafts to conquer, and fight off hordes of blue spiders.
I feel like going out on a boat for the day, wandering through the murky swamp pools, and stay in a mushroom base for the night (I love instant-mushroom bases, red mushrooms and bonemeal are an exploring essential now).
I want to go to a ravine, and build a bridge across it to a small house, or follow a river over the horizon.
I second this. I love the new update. Yeah, it's buggy, but this is the pretest. The game has much more for exploring now. Abandon villages and mines, huge ravines to explore and rivers to follow, hunts for animals so you don't starve, and how your always watching your back to make sure there isn't an Enderman stalking you.