This'll make future BZPCs a bit more interesting, especially with tripwires.

I haven't really been following the pre-release news.

Whats some of the major changes

Emeralds, trading with villagers, writable books, tripwires, some new blocks, EXP tweaks, interactive item tweaks, new terrain features, and an optional bonus starting chest.

Emeralds, trading with villagers, writable books, tripwires, some new blocks, EXP tweaks, interactive item tweaks, new terrain features, and an optional bonus starting chest.

Nice. Any new Biomes?

Don't think so, but there'll probably be minor tweaks to them as well. Maybe the fabled Jungle Temples?

jungle temples were introduced in one of the pre-releases, so yeah, they'll be there.

desert temples, too.

there's also the "Large Biomes" option when generating a new world that.. well, basically generates biomes of absolutely massive size.

Oh, excellent! So I can finally build my massive Jungle Treehouse that spans a massive space without ever touching the ground and requires 20 hours?