A forum member from xda-developers has released a beta version of Windows Phone 7 Series Theme for 6.5 devices.
To use it, install the cab file, then click on the icon in the start menu.
To exit, long-tap on the right side of the screen.
Settings is also listed in the long-tap menu.
As mentioned, the theme is a beta version and some more features are promised:
– Pictures hub
– Office hub
– Games hub
– Integration with Steam
– Appointments tile
– Smoother interface
Visit Forum thread | Watch Video | Download: .cab file of the theme.