The save files from the games on your Wii's Virtual Console will not be transferable to your Wii U's Virtual Console, Nintendo revealed to Kotaku.

Recently, we learned of two big firmware updates coming to the Wii U this year, one of which will be the launch of the Virtual Console on the system. This news was accompanied by the fact that Nintendo will not let users re-download Virtual Console titles previously purchased on the Wii onto the Wii U for free. Instead, they'll have to be re-bought for a small fee: $1 for NES titles, and $1.50 for SNES titles. However, opting for this scenario will allow for GamePad support. 

Should you rather transfer your saves and give up GamePad support, you can still transfer your Wii data over to the Wii U and access your games and their saves through the Wii Menu.

Wii U Virtual Console Games Won't Work With Older Save Files [Kotaku]