What you need is the release description document which can be found at http://www.3gpp.org/ftp/Information/WORK_PLAN/Description_Releases/
at broad level the following is the list of feature appeared in release 9
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UID Details
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350014 Registration in Densely-populated area
380067 Customized Ringing Signal
380057 Public Warning System
390073 Enhancements to Multimedia Priority Service
400031 Support of Personal Area Networks and Enhancements to Personal Network Management
400032 Multi-Media Telephony Service enhancements
400034 User Data Convergence
410027 Protection against Unsolicited Communication for IMS
410032 IMS Services Centralization and Continuity
420016 Enhancements of IMS Customized Alerting Tone (CAT) Service
420020 Service Specific Access Control in EPS
380064 Support for IMS Emergency Calls over GPRS and EPS
400038 LCS Control Plane Solution for EPS
380071 Harmonization of Gq'/Rx for Common IMS IMS_Comm_GqRx_Harm
400039 MBMS support in EPS
420024 Access Network Discovery and Selection Enhancements
420025 GTP-based S8 chaining
33025 Access Security Enhancements
420027 Timed Graphics
420029 OAM&P 9
380086 Definition of 3GPP UICC services over the new high-speed interface
400035 Enhanced Home NodeB / eNodeB
420007 LTE enhancements
410023 Rel-9 Improvements of the Radio Interface
420011 Self-Organizing Networks
420002 Voice services over Adaptive Multi-user channels on One Slot
