It appears that a Q&A tester from TT Games didn't get the memo that Nintendo didn't want to show the redesigned Wii U controller until E3 and posted this photo on his Twitter page. The photo has been taken down since then and the now (might be too late) anonymous tester has changed his profile information on his Twitter page hiding his identity. It is possible that TT Games just got their Wii U development kit and he was simply posting a image of what the Wii U development kit controller looks like and didn't realize the changes made to the controller in comparison to the older version. A big mistake.
The controller itself looks a lot better, with the button placement moved and the Analog Sticks added with already confirmation that they are clickable, similar to the Xbox 360 controller. Not to mention the little square under the d-pad is very likely the NFC reader.
I'm a little disappointed that this "surprise" couldn't wait to be shown by Nintendo themselves since it's only about 17 days away from E3. Great news none the less!