It was not long ago that Microsoft gave the world a preview of what we can expect to come with the 'Mango' upgrade to the Windows Phone platform. During this same timeframe, Microsoft also released the developer tools for the new platform.
When Microsoft showed off 'Mango', because of the amount of new features being added, it did not have time to publicly show off all the small upgrades the update brings to the platform. Step in winphone7.info who has taken the time to dig through the developer tools and has found several new items that were not previously discussed. It is worth taking a look at the source link as there are many more updates not covered below.
One new additions is that the "Contact Card now has History pivot to see what communication you have had with the persons." This is a handy new feature that allows you to find your conversations by person, rather than having to open each individual communication tool and searching.
Another big upgrade is to the maps section of Windows Phone. The 'Mango' update will bring maps that now show traffic flow and also a 'nearby' button that will show you what is located around you. There is also an option to filter what is displayed when using the 'nearby' service.
These are just a couple of the new features that were not discussed previously that are coming to the Windows Phone platform with the 'Mango' update. You can view more of the hidden updates by viewing this link here.
Update: The source of these images and features clarified that "everything you see here can be see by anyone who has the new Windows Phone “Mango” developer tools installed with the new 'Mango' emulator."