I want to have code that detects if the device has the full version of Flash 10.1 and if not redirects to a different site that uses HTML5.
The Flash site includes a lot of video, but also lots of other AS3 stuff going on, so I am not worried about devices that do not support HTML5.
Maybe just a message that says this site requires flash or an HTML5 capable device when older phones etc visit.

I checked out Lee Brimelows tutorial which handles serving Flash video or HTML5 video using swfobject. What I want to do is possibly a variation on that. Detect Flash and instead of just serving another video actually redirect. Is that a good way to go? How would I do the redirect?

I also checked out and setup Tera-WURFL
Lee has a video http://gotoandlearn.com/play.php?id=130
is that a better way or is it making things overly complex?

So to sum up. Visitor comes to site, if full flash 10.1 (not flash lite) capable device it goes to Flash site, if not it redirects to HTML site.