All flowers have 2-5 different variations.
Bushy leaves (adds more leaves to each side of the block).
Decaying leaves turn brown (dead leaves).
Different size of grass (couple pixels to a full block tall).
Sand in beaches and oceans is wavy (both sand and red sand).
Cattails grow in shallow water (place sea grass on y-level 62).
Spruce trees in snowy biomes are covered in snow.
More variation in Nether foliage (vines grow berries).
Fully grown glow berries have flowers.
Nether ores (Gold en Quarts) blend into soulsand vally and basalt delta.
Magma and netherrack blend into soulsand vally and basalt delta.
Blue magma and blue glowstone in soulsand vally.
Weeds randomly replace grass (plains, jungle and swamp biome have special weeds).
More flowers in flower forest.
Luchier plants in jungles.

Features being worked on:
New flowers from The Wild Update concept art.


More features come in future updates.