HTML5 Placeholder jQuery Plugin
– by Mathias Bynens (a collaborator on HTML5 Boilerplate and jsPerf)
https://github.com/mathiasbynens/jquery-placeholder
Demo & Examples
http://mathiasbynens.be/demo/placeholder
p.s
I have used this plugin many times and it works a treat. Also it doesn’t submit the placeholder text as a value when you submit your form (… a real pain I found with other plugins).