The audio on the Wii U is another thing annoying me. My receiver is mid-range from a few years ago, and doesn't have HDMI inputs. This means I either a) put up with no 5.1 or b) have to buy a new receiver. Maybe I was short sighted all those years back not making sure it had HDMI, but it's a great receiver in general. Wish Ninty could have just stuck an optical out on the Wii U. And the reports of poor Wii audio support is not good news... with the low resale value of Wiis, I guess I'll keep hold of mine now to play Wii and GC games.
So, a good thread on the audio side of things on Neogaf. It seems surround for the Wii mode is also gone. No DPLII support even if the analogue out is used.