Set a Date field with Rules?
Re Dan Mantyla's comment, if your date field is not a Date (UNIX timestamp) or Date (ISO) field but just a normal Date field, the following code works for me:

$thedate = $data['components']['date']['value'][0].' 00:00:00';

// set the date
$entity_created-&gt;field_date[LANGUAGE_NONE][0] = array(
    'value' =&gt; $thedate,
  );