OviMap application (with GPS), and another is the weather application. There is also a chat window I have open that shows threaded SMSs I am having with Jarvo.
So what's the learning time? I think about 3 to 4 hours before you start customizing it the way you want. If you have a technical background, then it will probably be down to about 1 to 2 hours. This is to understand how the menus work with the desktop, and how to understand how multitasking works. The Nokia Maemo website has tutorials. Don't worry about going through these if you have the phone, as they're already listed in the web browser's bookmarks.
What's missing so far?
- Speech directions when using the OviMaps for navigation.
- MMS (but that appears to be coming soon).