The guy who did the Verge review, Nilay Patel, did an AMA on reddit.com, where he was asked about the strength of the magnets on the leather loop and if it became loose. He said that it didn't and that he loved the band. This was my main concern. He also says a lot people told him it looked ugly, but from the video review he did, it looked like the critics were ladies from some fashion magazine, which I personally couldn't care less about.
I'm still enthused about the leather loop and I think the picture above is simply the result of the reviewer not having attached it securely.
I just hope the leather loop isn't delayed, like the briefly-displayed shipping estimates on the German website suggested. Although I'm only concerned with the US market, I think it would be a major fail of Apple to not have all variations (aside from the Edition which they said would be in short supply) available at launch.