Windows Live Photo Gallery Wave3 Beta was released few days back along with other Windows Live apps. Let us see what are the new features in this new version of Photo Gallery.
New user interface : If you have been using Windows Live Photo Gallery earlier, the first change you’ll notice is the User Interface. Toolbar is more cleaner and some buttons like rotate, delete are at bottom right. Overall now it gets a Simpler look. You can adjust the Navigation Pane (located on left side) or completely close it by dragging the separator near the vertical scroll bar. If all folders etc. in the Navigation Pane are collapsed then you’ll not get the vertical scroll bar, So just move the mouse around the navigation pane to view the separator which can be adjusted to alter size of Navigation pane or double clicked to completely close the Navigation pane.
Also you can close the Info pane (situated on top right) by clicking the ‘Close button’ or the ‘Info’ button situated on the toolbar. Now to get back the Info pane, you can click the ‘Info’ button again. I have seen many people confused in getting back the Info pane when closed using ‘Close’ button.
And in the Info Pane you can adjust the Information section (situated on bottom right) by adjusting the separator or you can collapse it completely by clicking on the blue arrow which gets visible when mouse is moved over that separator.
So what I am trying to say is, you can get the complete area occupied by display area of your photos by closing these panes. 
People tagging : This is the feature, I like most. Whenever in a photo , people’s faces are there , Photo Gallery detects the face and puts a square around it so that you can tag that person by entering the name of that person or if you are signed in to Photo Gallery then you will also be provided with your WL Messenger and WL Mail Contact list in the form of drop down appearing next to person’s face..............................CONTINUE AT SOURCE
Source : People tagging and other new features in Photo Gallery Beta