The simplest change here is the serialisation type pulldown. You can now select N-Triples for preview (and export). Unfortunately N3 doesn't work yet, although the interface elements are in place.
The other addition is the bookmark window, which requires more explanation.
First, open the bookmark tray (rightmost icon on the toolbar).
Anything that can be dragged onto the model can be dragged into the bookmark drawer. Bookmarked items have icons to show their types:
This shows (from the top):
At the bottom of the bookmark drawer is a check box called 'auto add from model'.
Checking this will automatically add bookmark items for items dragged into the model. For example dragging 'name' onto a connection will also add 'name' to the bookmarks - unless 'name' is already bookmarked (this prevents nasty duplication problems).
Bookmarks can be more useful still. Specifically: if you select a type or property bookmark then nodes or connections (respectively) will be added accordingly. For example:
Here I have selected the 'subject' property bookmark. When I added connections to the model (using the 'Add Connection' tool) they were added as 'subject' rather than '--none--'.
The document size can also be adjusted using the info window. If no objects are selected then the document size is displayed, where it can be adjusted. Note: the model doesn't resize automatically, yet. Some parts may be hidden after changing the document size.
Items can be removed from the schema window (this has a little bug, but generally works).