The list of past phone calls is now a single list, and cannot be separated into inbound, outbound or missed calls
Windows Phone does not support USB sync with Microsoft Outlook's Calendar, Contacts, Tasks and Notes as opposed to older versions of Windows Mobile with Desktop ActiveSync. Syncing Contacts and Appointments is done via cloud-based services (Windows Live, Google, or Exchange Server), and no method to sync this information directly with a PC is provided. Third party software, such as Akruto Sync, provides some of this functionality. A petition to Microsoft was filed to reinstate USB sync for Outlook.
Cut, copy, and paste
Partial multitasking for 3rd party apps
Connecting to Wi-Fi (wireless) access points with hidden SSID, but without WPA
Tethering to a computer
Universal email inbox
VoIP calling through a separate app
Removable SD cards
Bluetooth file transfers
Connecting to Wi-Fi (wireless) access points with both a hidden SSID and WPA protection
Sideloading for corporate apps
VoIP and IP Videocalling integrated in the Phone app
Support for Office documents with security permissions
Full Exchange support
Full background multitasking
IPsec security (VPN)
System-wide file manager
The 'Weekly' view in the Calendar app
List of features removed in Windows Phone Wikipedia
While Windows Phone contains many new features, a number of capabilities and certain programs that were a part of previous versions up to Windows Mobile 6.5 were removed or changed.
Until Windows Phone 6.5, the previous version did always cover the complete feature range of the predecessor version.
The following is a list of features which were present in Windows Mobile 6.5 but were removed in Windows Phone 7.0.