Apple further embraces social networking in Mountain Lion by adding an easy way to share photos, videos, and URLs using a new feature called Share Sheets. This feature makes it simple to share with friends through Mail, iMessage, AirDrop, or a supported website such as Facebook or Twitter.
Sharing options are content, context, and destination sensitive. If you're looking at a Web page in Safari, for example, you'll have options to share via e-mail, message, or Twitter. Share Sheets aren't a new concept. Eventually, however, you can expect them to support drag and drop. Apple has created a Share Sheet API and it's obvious that third-party developers will be coming up with new ways for people to share content.