Check out the video and the full changelog of Windows Phone Tango which follows:
The new features of Windows Phone Tango include
- Call forwarding – forward your calls to a designated number for
- all calls
- when I don’t answer
- when I am busy
- when my phone is turned off
- Call waiting – enable/disable
- SMS delivery confirmation – on/off
- MMS delivery confirmation – on/off
- SMS Character set – Reduced (no accents, standard SMS) or Full
- Send MMS acknowledgement – on/off
- Internet Sharing (Wi-Fi tethering)
- Enhanced MMS – Send voice notes, multiple images, video
- Nokia branded Marketplace icon
source - WPCentral