Tinhte today released the above video that demonstrates what seems to be iOS 5 running on a
white iPhone 4 white iPhone 5.
Gone is the spotlight search (I never used this feature, did you?), and instead of multitasking comes an expose style page that lists open apps.
Update: A second video posted by the Tinhte crew may indicate that the iPhone in use is in fact an early prototype of an iPhone 5. The iPhone has a 64GB storage, a different camera, and different buttons to that of the iPhone 4.
The second video also shows a different handling of the folders feature within iOS.