Here is a list of features as listed on MSDN.

Visual Studio 2010

VS 2010 Professional with MSDN

VS 2010 Premium with MSDN

VS 2010 Ultimate with MSDN
Product Features
Team Foundation Server
Version Control
Work Item Tracking
Build Automation
Team Portal
Reporting & Business Intelligence
Agile Planning Workbook
Test Case Management
Visual Studio Team Explorer 2010
Development Platform Support
Windows Development
Web Development
Office and SharePoint Development
Cloud Development
Customizable Development Experience
Testing
Unit Testing
Code Coverage
Test Impact Analysis
Coded UI Test
Web Performance Testing
Load Testing
Database Development
Database Deployment
Database Change Management
Database Unit Testing
Database Test Data Generation
Debugging & Diagnostics
"Pinnable" DataTips for easier data inspection
Post-mortem debugging support for .NET (dump debugging)
Breakpoint improvements (search in Breakpoints window, label, import/export)
New WPF visualizer
Enhancements for debugging multi-threaded applications (Parallel Stack and Tasks)
64-bit support for mixed-mode debugging
Static Code Analysis
Code Metrics
Profiling
IntelliTrace (Historical Debugger)
Architecture and Modeling
UML® & Layer diagram viewer
Architecture Explorer
UML 2.0 Compliant Diagrams (Activity, Use Case, Sequence, Class, Component)
Layer Diagram and Dependency Validation
Lab Management
Test and Lab Manager
Virtual environment setup & tear down
Test Case Management
Manual Test Execution
Manual Test Record & Playback
Lab Management Configuration