Here are some of my favourite new tools and improvements that have come with the 10.1 release. These should make your mapping and workflows just that much more enjoyable.
1. Searching for a projection
With ArcMap shipping with over 4000 projections, it is easy to feel a bit overwhelmed, especially if you are a new user. Although you have always been able to save the frequently used projections to your favourites, you can now input keywords and find exactly what you are looking for. If you have no idea what you are looking for, you can even let ArcGIS use your current extent to suggest the best projection.
2.Enable Editor Tracking
Trying to figure out who moved that feature without telling you? Now with Editor Tracking enabled on your feature class, any new features or modifications will be logged with the username and time/date of creation or modification. This works with SDE databases as well. This is going to make your metadata housekeeping a lot easier. Note: This will not tell you if a feature has been deleted – best to use versioned geodatabases for that.
3. Geotagged Photos to Points
Point to a folder with geotagged photos, and ArcMap will convert the EXIF information to feature points with the photos as geodatabase attachments. Create an HTML popup from the created file path field and presto, you have an interactive map with georeferenced photos.
4. Key Numbering for Labels
In highly feature-dense maps, it may be difficult to label all the features descriptively. It is now possible to automatically set these features to use key numbering – in other words, assigning an index to features, and labelling feature with the index instead. By the way, the Maplex Label Engine is no longer a separate extension, but part of the core software!
5. Dynamic Legends
The feature that I think everyone has been waiting for! Now if you have a feature class with numerous symbol classes, ArcMap will automatically determine what is in the visible extent and only display those legend items – perfect for those data-driven pages.
Try these out today! Any questions, let me know in the comments section.
Ebony
Esri Australia Technical Blog 
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