Tateru Nino has and article out on the coming new viewer. See: Say goodbye to the side-bar. Rhett Linden talks Second Life UI redesign goals. I got it and took it for a spin. The image here shows the new user interface.

You can see the new 3.2.1 Viewer interface, if you are using the Development Viewer. It has a few problems:
Known Issues:
o The Viewer floater camera views and presets do not work.
o The Nearby Voice panel does not update to a new call or from
nearby voice info once opened.
o Viewer crashes when updating UI size in preferences.
o The Speak button is activated when dragging and dropping between
toolbars and/or moving back to the Tool Box.
o Viewer crash when moving the speak button from one toolbar to
another when there is an active call request.
o Teleport history doesn't display visited locations.
o Viewer crash when double-clicking the mini-map in People > Nearby.
o Notification and conversation chiclets overlap.
o WASD controls don't move avatar while the Move floater is in focus.
o Closing voice controls while a group or p2p call also closes the
group call/IM window
o Viewer crash after teleport
o Hitting back in the 'Create Group' panel or 'Blocked' panel
requires multiple clicks for action to occur.


