Longhorn Air7 Beta, an updated version of the first Longhorn style theme for Windows 7. In my opinion, this has been one the top 10 Windows 7 themes till now.
Update:
Item Buttons
Animated Shellstyle
Taskbar Text Glow and Color
Back/Forward Buttons for Explorer and Internet Explorer 8
Adressbar Style
Progress Bars
Clear Design Navigation Buckground (Navbar)
What's New: 
Redesigned Nav Background buttons
Adressbar Text size with very clear font
Clear Back/Forword Buttons
Aura Shine ShellStyles
Big and Colored ShellStyle Text (Thanks to sunbeem2000)
Windows Shadows
Clear Adressbar
Taskbar
More Clear Start Menu
Curved ShellStyle
Smooth Text Colors in Explorer
x86: Patched UxTheme Files for Windows 7 RTM Build 7600.16385
x64: Patched UxTheme Files for Windows 7 RTM Build 7600.16385
[How to] Apply a third-party theme in Windows 7
www.vista123.net, easily tweak and customize your Windows Vista.
