CORS does not seem to work for uploading files from the browser.

I'm not entirely sure how to properly format code on here, but here's the request bit (with the irrelevant success and error functions stripped).

$.ajax({  
    url: "https://api-content.dropbox.com/1/files_put/auto/Apps/The Worm/" + file.name,  
    headers: {  
        Authorization: 'Bearer ' + dropbox_token,  
        contentLength: file.size  
    },  
    crossDomain: true,  
    crossOrigin: true,  
    type: 'PUT',  
    contentType: file.type,  
    data: evt.target.result,  
    dataType: 'json',  
    processData: false  
});

I had looked at the Javascript SDK, but it looks like you can't just put a token into the client to use, and I don't want to have to re-OAuth each time.