Two out of ten nine. NFS:MWU and ZombiU.
Whoops, I only count nine games now... and there seems to be a confusion what is third party, as many games listed are published by Nintendo. So the rest of my retail games are: NintendoLand, NSMBU, Pikmin3, W101, SM3DW, TLoZ:WWHD, WiiPartyU
If I look at the digital side I'm 100% third party with the eShop: Edge and Nano Assault Neo.
Although I might get WiiFitU with the purchase of a FitMeter on January if I like it during my Xmas testing.
WiiU's Virtual Console is 100% Nintendo, all from the trial campaign.