They definitely run a little big.  I believe thats the intention.
My measurements are -Bust is 41 inches- Waist 38 inches- hips 44 inches
The sizing chart indicates I should order a Large.
Well with my experience with Cherokee brand tops... they run big.
I ordered a Medium.  It fits the way it should according to the style.
It's "buffy" in the middle area of the shirt (around the bust and waist area)
Other wise it fits great.
Order one size smaller than the sizing chart shows and you should be pleased.