I'm not a big fan of stringly typed objects, even though js doesn't really provide any good built-in alternatives like enums.  I now have to go read everything that references this variable to figure out what the valid types are for it and what they mean.  A better way might be to make a "type" variable, maybe something like this:

```js
var layerType = { none: 'none', neighborhood: 'neighborhood', location: 'location' },
    currentLayer = layerType.none;
```
Then of course whenever you set currentLayer you use layerType.whatever.  This obviously can't be enforced by the language, but it makes it clear to the reader what the expected values are for it and lets you add comments explaining what they mean.