Windows Phone 7 "Mango" Update Features

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It doesn't appear to have a release date scheduled yet, but at least some of the "Mango" features have been talked about. Here's a quick list of what's to come so far in the new update:

Office Integration with SkyDrive and Office 365
Pinning Email Folders to the Start Screen
Conversation View in Email
Email Server Search
Lync Integration
Complex password support
Information Rights Management support
Support for access to hidden corporate Wi-Fi networks

This comes direct from the official blog: http://windowsteamblog.com/windows_phone/b/windowsphone/

From another site, these features were mentioned:

Facebook Chat/AIM/Live Messanger support
Group Messaging
Visual Voicemail
Improved Xbox Live game data sync
Lockscreen option to show album art of playing audio tracks
Multitasking (webOS style)
Internet Explorer Mobile 9
Twitter Integration

http://www.geek.com/articles/mobile/windows-phone-7-5-adds-facebookaim-chat-visual-voicemail-skydrive-support-20110516/

It looks like it's shaping up to be a big realease.