I based my chosen size on previous reviews, which stated that the arm holes/ shoulders were narrow.  Nope!  It pretty much fits just like the picture shows (including the length), maybe even a bit larger on me through the shoulders.  I am about a size 6, approx. 34 B bust, 5'9 -- I ordered a size M.  I am getting used to how it fits/ looks on me-- it's very comfortable but if it doesn't shrink a little in the dryer I might take it in to get it tailored slightly through the chest.