Rotate Viewport

[jaberwok]

to answer the original question as an update. If you are on subscription, you have access to the 2009 bonus tools, and included among those few tools you will find that you can now rotate a viewport, and it will twist the ucs along with the new orientation of the viewport.

and now included in 2010 - hooray!

[jaberwok]

In AutoCAD 2010 you can use the normal rotate command on a viewport. It will automatically rotate the view with it.

The setting that controls this is VPROTATEASSOC

and now included in 2010 - hooray!

Snap!