A tester's Twitter post shows a picture of a Wii U controller with analog sticks.
The Wii U controller may have traditional analog sticks, as opposed to the Circle Pads from the model shown at E3 2011, according to a photo posted by someone claiming to be a QA Tester at TT Games.
The unit also shows the + and - buttons moved to a more reachable position below the A, B, X, and Y buttons, similar to the layout of the DS Lite and DSi, instead of on the sides of the Home button below the screen. An additional unmarked button is located next to the Power button and an unidentified square resides below the D-pad. The headphone jack and stylus slot have been relocated and the controller appears wider overall.
The controller matches European filings for an alternate Wii U controller design that were filed simultaneously with the design shown at last year's E3. Both designs were filed on May 12, 2011 and published on February 2 of this year. Not visible in the photograph are contoured handles on the reverse of tablet.
TT Games is currently developing Lego City Stories for the Wii U. The tester's Twitter post and photo, which showed the controller connected to debugging hardware, were quickly removed. It is not certain whether the controller represents an intermediate design or one closer to the final version.
Thanks to Caterkiller on the forums for the tip.