Add Placeholders To WordPress Login Form And Remove Labels

ks-custom-login.js

// ----------------------------------------------------
// Adding the placeholders in textfields of login form 
// ----------------------------------------------------


jQuery(document).ready(function($) {

	$('#loginform input[type="text"]').attr('placeholder', 'Username');
	$('#loginform input[type="password"]').attr('placeholder', 'Password');
	
	$('#loginform label[for="user_login"]').contents().filter(function() {
		return this.nodeType === 3;
	}).remove();
	$('#loginform label[for="user_pass"]').contents().filter(function() {
		return this.nodeType === 3;
	}).remove();
	
	$('input[type="checkbox"]').click(function() {
		$(this+':checked').parent('label').css("background-position","0px -20px");
		$(this).not(':checked').parent('label').css("background-position","0px 0px");
	});

});

Hi !

This is old but usefull, I'd suggest a little modification : instead of writing 'Username' and 'Password' in english, I got the content of labels to put in placeholders. It's "better" because it will take language into account automatically, following wordpress lead.

Just replaced the start with :

placeholder_login = $('#loginform label[for="user_login"]').html();
placeholder_password = $('#loginform label[for="user_pass"]').html();

$('#loginform input[type="text"]').attr('placeholder', placeholder_login);
$('#loginform input[type="password"]').attr('placeholder', placeholder_password);

@Rancebrume

That's pretty sweet, but I think using html() also adds the actual form field to the placeholder.
I've used this instead:
placeholder_login = $('#loginform label[for="user_login"]').text();
placeholder_password = $('#loginform label[for="user_pass"]').text();