Some may be more obvious than others, I'm a 'newbie' so I only just noticed most of this ^o^

Stones-
There is a circle of stone statues at the ruins that look like the statues off the anime film, spirited away.

Trees-
There is a circle of these huge trees in in the center of it is a dip filled with loads of blue flowers. A perfect place for sleeping unseen.

Underwater-
I found a place on the edge of the river bank where you can sleep underwater without turning into a frog.

Field-
In the center of the forest there is a field full of grass where deer only pass by, to be honest its a great place to play ^^

Mask-
One of the masks you can get for your deer is like the one on the deer god, or 'night walker' off the anime film: Princess Mononoke.

Dance-
The more deer that join the dance, the better the music in the back ground is.

Butterflies-
One of the purple flower patches is surrounded by butterflies. Pretty O_O

Robin-
I saw a robin fly past me. I don't think we can shapeshift into robins yet?

Shapeshifting Fairy Circle-
If you have drunk from the shape shifting fountain, then you run/fly/hop out of the fairy circle surrounding it, you will turn back into a deer!

Pond-
Some times dragonflies like to skim across the surface of the pond!

Sorry if this may be obvious to more experienced players I just had to say! ^^
Oh wait, one more thing.

Endless Forest-
The forest is EPIC!