Mac/iOS: Evernote's simple image annotation tool, Skitch, received an update today. It adds two new annotation features that make it easier to quickly provide feedback.
The first new feature, Stamps, adds the ability to quickly add simple sentiments such as "Yes", "No" or "Perfect" to an image with images and a bit of text. If you get a lot of images back that you need to do a quick run through and approve, this works great.
The second feature, PDF annotation, is only available for Evernote Premium customers. This adds the ability to mark up any PDF in Skitch the same way you do with images. The new features come to both the iOS and Mac versions of the app.