How well you take criticism can be critical to your success, especially when it's perjorative. But, as author and entrepreneur Seth Godin states, getting little to no feedback can be much worse hearing from someone who doesn't like your work.
Godin stresses that your work should elicit some sort of reaction. If the one you get is lukewarm or indifferent, then it's possible that your work is mediocre as well.
Note that this applies to giving criticism as well as receiving it. If you don't like a colleague's work, telling them so -- respectfully -- could help a lot more than just a passive "OK".