I'm Jewish so I can give you my point of view, but there are many other people who may feel differently. For me this is simply a troll doing something that he thinks is funny and slightly inconveniences the mods at osm. Calling certain areas "Jewish" is not antisemitic in the way that is in any way dangerous. Here is a joke from Jews about how Teaneck is Jewish [1], nothing antisemitic about that. Here is a joke about Israel being Jewish [2] .

But lets just say that this was antisemitic. So what? Trolls do offensive things online all the time. OSM was properly alerted to it and quickly reverted it.

[1] http://photos1.blogger.com/blogger/3613/1194/1600/teaneck.jp...

[2] https://johnjohns1.fjcdn.com/pictures/ish+conspiracy+could+m...