Clicking the Share icon will launch a new panel. No longer will you be taken to a special "Get a Link" page. Additionally, there is no sub-menu anymore. Sharing to Facebook, Twitter, Google+, and Email can be done from this panel.
Additionally, you can get a link to a specific photo side, create an HTML5 Embeddable slideshow, or get a link to the shopping store.
"Collect" has been moved to the Tools menu (the wrench).