Embedding a video source from Vimeo is as simple as adding the Vimeo URL to the source tag, specifying the type to be video/vimeo and including the data-engine="vimeo" attribute in the video tag:

<div class="jw-settings" id="my_simple_settings">
     <video id="my_simple_video" controls data-engine="vimeo" poster="/posters/428916440_640.jpg" preload="none" >
          <source src="http://vimeo.com/61702922" type="video/vimeo" />
     <div class="jw-modes">
          <div class="jw-mode" data-type="html5"></div>
          <div class="jw-mode" data-type="flash"></div>

This results in the following Vimeo video being wrapped in the JW Player.