Just off the top of my head, some of the differences are:

-Dolby Pro Logic IIz decoding
-Anchor Bay ABT-2010 advanced analog and digital video 1080p/24fps/60fps upconversion and deinterlacing with multi-cadence detection
-Audyssey Dynamic Surround Expansion for a more enveloping soundstage with front width or height channels – World’s First with DSX
-Audyssey MultEQ XT, Dynamic Volume, Dynamic EQ (it can be purchased for the 3808 for $100)
-Six HDMI inputs, dual HDMI video output

How much is the 3808 going for now?