Ack— I meant to say the wife ISN'T such a treat. :P

Err…I don't know if I'd call the couple “cute”. The wife is such a treat.

No prob!

It could also refer to an outfit, yes, but considering how heavily laden the video is with pop culture references, I doubt that's what it is referring to. Also, One Piece has been running in Japan since 1997—it's surpassing Dragon Ball Z in comic book content and television episodes. I have quite a few Japanese friends who aren't interested in anime at all, but at least know of One Piece and associate 「ワンピース」 with such.

That's true, but considering how pop culture heavy the video is, I wouldn't be surprised if it referred to the actual anime. One Piece is so big in Japanese pop culture that even my Japanese friends who aren't into anime saw the video and thought of the show, not an outfit.

The 「ワンピース！」 in Gaga's video refers to a very popular Japanese anime/manga called “One Piece” by Eiichiro Oda. I was so surprised to even see it in the video—I had to rewind to make sure I read the katakana correctly, haha!