One of the biggest gripes players have had with Counter-Strike: Global Offensive up to now has been the hitboxes. The problem was made really apparent a few months back when someone made a gif of a crouched player being shot repeatedly at point-blank range and yet, taking no damage.
At the time, Valve said that it would work on fixing this but it had no timeline. Now, the hitbox patch has officially dropped. The latest Counter-Strike: Global Offensive patch update on steam addresses both hitboxes and animations after “much community demand”.
Valve also got to work on weapon models poking through walls, which could often give away your position in a competitive match. After this patch, your weapon models should no longer poke through parts of the map. This issue was most apparent with the M4A1-S, speaking of which, that gun will no longer cost as much to buy, but it will have slightly increased bullet spread.
You can find all of the patch notes for yourself, HERE.