I’ve come into this problem a few times while building out sites so I’ve built a quick function to automatically calculate and resize (height) videos on your blog/website.  This is especially helpful on a site chalk full of videos like craiggoodwill.com.  Without further ado:

[javascript]function resize_video() {
// this function is helpful when using a dynamit width on your iFrames for YouTube or Vimeo videos to automatically adjust the height
$(‘.video iframe, .video object, .video embed’).each(function(){
var width = $(this).width();
var vidheight = (width * 0.5625);
$(this).css({height : vidheight});
});
}
[/javascript]
Then call your function on both load and resize.
[javascript]
$(window).load(function(){
/* do the resize on load */
resize_video();
});

$(window).resize(function() {
/* do the resize on orientation change as well */
resize_video();
});
[/javascript]