I found that in Moodle 2.3, with strict PHP, there were some errors that prevented the cron process from completing and finding the locations of users.

I was able to fix this by modifying the code as follows...

if (isset($xml->geoname->lat)){

    $boumc = new stdClass();

    $boumc->userid = $user->id;

    $boumc->lat = floatval($xml->geoname->lat);

    $boumc->lng = floatval($xml->geoname->lng);