Want to get an idea about what contributions are happening in OSM in your region? Maybe you're even looking for a way to better review map changes (hint, hint)? A good starting point is probably my latest-edits page tool. It displays all objects that have been modified during the last week alongside with their respective changesets.
One major drawbacks of the tool was that until recently, deleted map objects (and changesets consisting solely of deletions) were not displayed on the page. Now, deleted objects are displayed as faint "ghostly" outlines on the map. In the same way, you can now also see how modified objects looked like before the respective contributions happened. This can result in a nice looking "shadow" effect when for example buildings have been realigned to better aerial imagery.
Also, you can now select between the latest changes from the last day, week, or month, and directly zoom to the location of a particular changeset:
The tool still doesn't show intermediate states of objects that have been modified more than once in the selected time period, as well as modifications to relation objects.
Programmatically, this new version is implemented by using an Overpass augmented diff query (switching over from a "regular" OverpassQL query using the
newer statement) and some massaging of the returned data to get them properly in shape (it sorts the data into two buckets – one for the state of the data before the respective edits and one for the current state – then uses osmtogeojson to generate GeoJSON which can be put on the map).