As an A3 saloon owner I still think it looks better externally than the new A4, not sure if it's the longer doors but it's the side profile that puts me off.
I'm really warming to the Avant though, the S models look gorgeous.
Interiors, while BMW like, the finish is lovely, watched a few you tubes and the S4 Avant (if I had the cash) would be a nice upgrade from my tdi. All VW emission jokes aside would need to look into the mpg of an S series avant compared to my salon as while it may be killing the environment I'm definitely going to the pump less than my old 2005 A3, while it will never reach the mpg suggested, it's still impressive.
But back to the A4, in the right spec I think she is starting to warm on me. Interesting how the blue above looks a lot richer on the iPhone pic, very nice...