Nintendo has added a section to its UK website confirming that Nintendo TVii will be coming to European Wii Us, though there are no specific details:
Nintendo TVii will be available in selected regions throughout Europe in 2013.
More details will be announced in due course.
While “selected regions” is pretty vague, it's probably safe to assume that the UK is one of them. But that's a pretty big launch window, so TVii could arrive anything up to a year after the Wii U itself launches in the UK on Friday (November 30th).
TVii is an app for the Wii U that will turn your Wii U GamePad into a sort of universal remote for content to which you're subscribed.
Nintendo TVii enables you to find, watch, and engage with TV shows and movies in entirely new ways.
Using the Wii U GamePad, you can browse and search for programming from sources you subscribe to, including cable and satellite channels and video-on-demand services.
Presumably in the UK those services will include things like Sky and Netflix UK.
TVii was originally going to be exclusive to Wii U owners in North America, but even they don't have it yet as it was dropped from the launch line-up of apps at the last minute.