Worksharing display was added to Revit a few releases ago, but it still seems to be rather under-used.
Which is a shame, really - it's easy to use, and when set up properly can give users quite a bit more insight as to what's going on in a Workshared project.
The controls for Worksharing Display are found in the View Control Bar at the bottom of every Revit graphical view:
From this menu, you can set the display mode for the current view and turn Worksharing Display off. You can also modify the Display Settings:
Note that you can configure the view to show the checkout status of objects (objects that you own and objects that others are editing will be displayed with different colors), owners (who, specifically has each object - again by color), model updates (what objects have been modified and saved back to the Central File or deleted since you last synchronized your own model), and finally each specific Workset can be displayed with its own color.
There are two modes I find particularly useful. The first, Checkout Status is shown below.
In this example, this is showing me that I own the water closets (shown in green) and someone else is currently editing the floors and door (shown in red). This is really all I need. I don't care really who owns the objects - just that they are currently being edited by someone.
The other mode I like is Model Updates:
This shows me that the floor in red has been deleted from the Central File, and the door and the other floor (in blue) were modified. Using this mode, I can see how out of date my local file might be and use it as a guide as to whether or not I should perform a synchronize or "reload latest".
A Few Words About Performance
Worksharing Display requires that your local file regularly "ping" the Central File to get updates as to objects' status. If you are working in an environment where you are experiencing a lot of latency (lag) on the network, or if you are working in A360 Collaboration for Revit, you may not want the Worksharing Display to "phone home" quite so often as this can cause you to experience frequent pauses while it does so. Revit will appear to "hang" for a few seconds. You can control the frequency of the updates in the Revit Options:
The default setting for this is shown in the image above. The slider is all the way to the right, meaning that I'm getting updates every 5 seconds. You can move the slider to the left to increase the time between updates to as much as 60 seconds. Sliding it all the way to the left disables automatic updates; you will only get an update when you synchronize or borrow objects.
Additionally, I would not recommend setting this mode for all views. You should consider having a dedicated view for Workset Status that you can refer to periodically instead.