title: GWT Element setAttribute vs setPropertyString
body: <p>I can't determine the difference between <code>Element.setAttribute(String name, String value)</code> and <code>Element.setPropertyString(String name, String value)</code>. Is there a difference? Which is preferred when attempting to set, say, a placeholder on a text input? I've been doing <code>getElement().setPropertyString("placeholder", "this is a placeholder");</code> and it works, but is that the appropriate way to do it? </p>
  
  <p>In the <a href="http://google-web-toolkit.googlecode.com/svn/javadoc/latest/com/google/gwt/user/client/DOM.html" rel="noreferrer">documentation for DOM</a>, <code>setAttribute(Element, String, String)</code> is deprecated, saying to use "the more appropriately named <code>setElementProperty(Element, String, String)</code> instead." Does that imply that one should be using the similarly named methods of <code>Element</code>?</p>