A question came up on the discussion groups today, and I thought it would make a pretty good blog post.
Somebody wanted to know what happened in 2009 to the pull-down that you could use to change the scale of a viewport. It's still on the Viewports toolbar, if you want to turn that on, but at first glance it doesn't appear to be in the new Ribbon-based environment. (Another reason why second glances can sometimes be very helpful.)
It turns out that the viewport scale control is another context-sensitive bit of the user interface, like the mtext and Block Editor Ribbon tabs. When you have a viewport selected, or when you double-click inside it, a control appears on the right-hand side of the status bar.
In the image above, the viewport scale is 1" = 1'-0". If you look for this without having a viewport active, it won't be there, so pay attention!
Also, if you have Quick Properties turned on, one of the default listings for a viewport is its scale -- another quick and easy place to make the change.