So, I decided to finally play a snapshot. I've skipped all of the snapshots previous to 18w11.
It's a fair sized island, with a plains biome and a lot of beach.
A single oak tree on the island, and a load of caves to explore.
But the real fun parts are in the oceans around the island. Within 100 blocks of the island in any given direction are three shipwrecks, a small ruined village, an ocean monument, and with the right render distance the end portal stronghold room can be seen at the bottom of the ocean from the shore.
I haven't really fully explored it yet, as I just started it last night, but I'm working on it, so there might be more fun stuff to share later. :]