I take a 7.5 in almost every shoe.  I'd been reading the reviews for this for a long time, and when a size 7 in this aqua color popped up I bought it right away.  Unfortunately it is much too tight on my right foot (the left one is tolerable).  I am sending it back.  Otherwise the color is good and the style is really cute; even though it's a bootie, it would be a cute summer kick and has nice rubber on the bottom for traction.

However, I'm back to report that this boot is simply not destined to be mine.  Someone must have returned a pair of 7.5 in the apricot color, because they were listed at only 19.99.  I bought them, assuming the sizing would be better, and it's still too tight on the right foot.  They're going back.  If you want them, keep your eyes peeled!  They may drop below what I paid!