Apple is working on a new feature for Safari in Apple's Mac OS X Lion that will bring a different kind of bookmarking functionality to the browser. Apple calls it "Reading List" and is meant to offer users a way to save pages for later reading. The new feature is described by Apple here:
Reading List lets you collect webpages and links for you to read later. To add the current page to your Reading List, click Add Page. You can also Shift-click a link to quickly add it to the list. To hide and show Reading List, click the Reading List icon (eyeglasses) in the bookmarks bar.
And the accompanying eyeglasses icon:
This feature is currently inactive and hidden within the latest Mac OS X Lion builds. Apple has not yet made any mention of the feature in any of their Mac OS X Lion documentation. The basic functionality would pit the feature directly against popular services such as Instapaper and ReadItLater. Apple's implementation appears to be partly based on HTML/js but it's not yet clear how robust a solution it will be. For example, one compelling feature of Instapaper and ReadItLater is the ability the synchronization of bookmarks across devices.