What exactly does the WiiU TV function actually do?

Well, as the title says, what does the Wii U TV guide thingy do? Has it been improved since launch? I have a Charter cable and a few of their boxes at home, will this feature work for me? What can I expect, since I have not bought a Wii U yet?

 

So nobody here has played around with the TVii function on the WiiU?

 

I have. But only with sports. It gives you updates on other sports games and statistics and stuff like that.

Never used it for regular TV though.

 

It's essentially just a tv guide. Incredibly useless.