Third party sales on Wii U aren't really as awful as they seem when you consider:
(A) The tiny install base.
(B) That most of those ports are late, and more expensive on Wii U.
Attach rates are actually really good; Batman Arkham City has a 5% attach rate on Wii U, which is about the same as its attach rate on 360. Assassin's Creed 3 has a similar attach rate between Wii U and PS360 also.
Wii U even beats PS3/360 in some cases; Sonic and Sega All Stars Racing has an 8% attach rate on Wii U, but only a 0.3% attach rate on PS3/360.
The only thing holdng back third party sales on Wii U is the overall small number of Wii U owners.








