Check out mediaelementjs for general video/audio support

[espaan]

On http://mediaelementjs.com/ there is a HTML5 video player (with fallback to flash/silverlight) that plays videos in a lot of browsers with the html5 video tag.

So you can just insert local videos with <video ..> and they work in a large set of browsers.
You can also display youtube and vimeo (there seem to be some bugs with vimeo) is the same manner: http://johndyer.name/html5-video-wrapper-for-youtube-and-vimeo-api-mediaelement-js/

Github project https://github.com/johndyer/mediaelement/
It has a MIT license, so can even be used as a Zikula Core vendor plugin !
And actively being developed.

See for an overview of video players also:
http://www.webaxe.org/accessible-html5-media-players-and-more/

Yahoo has a nice one too http://webplayer.yahoo.com/ but the license is a bit unclear to me.

There is also http://www.longtailvideo.com/jw-player/ but that one is only free for non-commercial usage and costs quite a bit for a single website..