Is it possible to use JavaScript to change the meta-tags of the page?

Question

If I put a div in the head and display:none, than use JavaScript to display it, will this work?

Edit:

I have stuff loaded in AJAX. And as my AJAX changes the

Answer 1

It is definitely possible to use Javascript to change the meta tags of the page. Here is a Javascript only approach:

document.getElementsByTagName('meta')["keywords"].content = "My new page keywords!!";
document.getElementsByTagName('meta')["description"].content = "My new page description!!";
document.title = "My new Document Title!!";

I have verified that Google does index these client side changes for the code above.