Nintendo has confirmed nothing, but IBM has, confirming that WiiU's CPU is at least based on a POWER7:

http://www.engadget.com/2011/06/07/ibm-puts-watsons-brains-in-nintendo-wii-u/

The GPU has also been confirmed to be a highly customized Radeon R700, with many reports saying RV770 specifically:

http://www.engadget.com/2011/06/14/wii-u-has-last-gen-radeon-inside-still-more-powerful-than-ps3-a/

More tech specs:

http://en.wikipedia.org/wiki/Wii_u

http://www.ign.com/wikis/wii-u/Wii_U_Tech_Specs

Specs from the companies who provide the parts have pretty much been "ballpark" confirmed, which is why the video earlier in this thread chose to use the lowest end processors/capabilities based on what we know so far for WiiU in the comparison to the current HD consoles... and its performance was still well above the PS360.

The thing is when the games arrive and for arguments sake lets say the WiiU has more performance in some areas less in others , making it overall on par with the PS360, We will still see endless comparisons ,some saying look these shots show how much better it is , followed by no they don't and reasons why and if the WiiU turns out to be more powerful it wont change a thing we will still get more of the the same .

@archbrix So now it's more powerful than what the video showed?

If these rumors were not true, why would they not just denounce them?? I get that they cant follow every single one, but when asked straight up about it???

If you want to keep the details about something a secret (to unveil it when you want) you can't constantly denounce rumours; because (through the process of elimination) people will find out what you're doing.

They dont have to adress every rumor, I already said they didnt. A simple yes or no, would have sufficed. Otherwise why say anything at all??? They could have just kept their lips sealed until E3

You can't just choose to answer rumours when the outcome is favorable and say "no coment" when the actual answer would be unfavourable to you (wheter the rumour being true or false), that would be just too simple to read.

If you want to be able to keep any secret at all you have to either not comment on any rumour or act randomly. Since the second option is not very productive and would probably piss a lot of people off, I think they're on the right track.

Sure, you could choose a few rumours now and then to coment, but you couldn't make a rule out of that, so you can't criticize a particular instance of them not doing that.

duplicate

Exactly 2 months until E3. Yep.

Why not just go with what actual real devs have said?

Nintendo has already said the demos were on early devkits so that means they are still working on them and that they would get better results in the final consol otherwise they would not have said “this is on early devkits”