There are a bunch of new features with the new series. Generally it depends on your needs. If you go to Denon's site, they have the ability of selecting and comparing the models and all the models are up there.
My opinion, the AVR4310CI is better than the 3808 in all ways, the 4308 however has a bit better amp section (though again features of the 10 series are better).
My opinion, the AVR4310CI is better than the 3808 in all ways, the 4308 however has a bit better amp section (though again features of the 10 series are better).