I’ve updated my Youtuber plugin to include an options page. This allows you to much more easily adjust the display size of YouTube videos to match your blog’s layout. This required a bit of hacking in the previous version. Youtuber generates valid XHTML and is extremely easy to use. If you embed all you YouTube video’s using this plugin, changing a few values in the options page will allow you to adjust the display dimensions of all the videos on your blog. This might come in handy if you ever upgrade or change your theme.
More info (as well as a download link for the new version) in the original post.