The Wii U Wiimote

I recently got an additional Wiimote, and noticed that the box that it came in is branded as "Wii U". However, the Wiimote that is pictured on the box, as well as the actual one, doesn't have any "Wii U" branding. But there are noticeable physical differences as you can see below.

The box says "Also works with Wii" despite the actual controller being branded FOR the Wii.

A part of the hand wrist strap looked different, as there is some kind of protruding material that you can use to push something with... which I assume is that new sync button outside the battery cover... which I found out a few minutes later after trying to sync the new controller that it is in fact its purpose. Not bad, since my puffy fingers with long nails can't to the job. The sync button inside the cover is still there. I should have also noticed the illustration showed on the TV when I tried to sync my old Wiimotes to my Wii U a while back.

I think that new external sync button is a nice addition, especially for those who would complain of having to open the battery cover whenever they need to sync the controller. That's something I have no need for, though, as I'm pretty much content on how to use the internal sync button. Besides, I always remove the batteries when the controller isn't in use, so I still have to open that battery cover from time to time.

Aside from the aesthetic changes, I'm not exactly sure how else this new "Wii U Wiimote" differs from the older ones. I do know for a fact that it still has the motionplus built in (because it's also written on the Wiimote itself). Are there any other changes?