[jquery] Change Placeholder Text using jQuery

Moving your first line to the bottom does it for me: http://jsfiddle.net/tcloninger/SEmNX/

$(function () {
    $('#serMemdd').change(function () {
        var k = $(this).val();
        if (k == 1) {
            $("#serMemtb").attr("placeholder", "Type a name (Lastname, Firstname)").placeholder();
        }
        else if (k == 2) {
            $("#serMemtb").attr("placeholder", "Type an ID").placeholder();
        }
        else if (k == 3) {
            $("#serMemtb").attr("placeholder", "Type a Location").placeholder();
        }
    });
    $('input[placeholder], textarea[placeholder]').placeholder();
});