Microsoft has announced that this will be the only beta version of windows 7. They have also announced the different SKUs. Here are the key features for all the different windows 7 versions. Microsoft has created a SKU line-up where each SKU is a superset of the previous SKU. This means that each higher edition SKU will have every feature lower edition SKUs have

Windows 7 Starter
Broad app and device compatibility with up to 3 concurrent applications
Safe, reliable, and supported
Ability to join a Home Group
Improved taskbar and JumpLists

Windows 7 Home Basic (emerging market only)
Starter features
Unlimited applications

Live Thumbnail Previews & enhanced visual experience
Advanced networking support (ad-hoc wireless networks and internet connection sharing)
Mobility Center

Windows 7 Home Premium
Home Basic features
Unlimited applications

Aero Glass & advanced windows navigation
Easy networking & sharing across all your PCs & devices
Improved media format support, enhancements to Windows Media Center and media streaming, including Play To
Multi-touch and improved handwriting recognition

Windows 7 Professional
Professional features
Unlimited applications

Ability to join a managed network with Domain Join
Protect  data with advanced network backup and Encrypting File System
Print to the right printer at home or work with Location Aware Printing

Windows 7 Enterprise and Ultimate
Professional and Consumer
Unlimited applications

BitLocker data protection on internal and external drives
DirectAccess provides seamless connectivity to your corporate network.  (requires Windows Server 2008 R2)
Decrease time branch office workers wait to open file across the network with BranchCache. (requires Windows Server 2008 R2)
Prevent unauthorized software from running with AppLocker

Note: Ultimate includes all Enterprise and all Home Premium features, including multi-language packs.

- Windows 7 Enterprise is available only through Microsoft Volume Licensing