[whatwg] HTML5 video element - default to fallback in cases where UA can't play format

[Kit Grose]

Thanks for the really in-depth reply; you make some excellent points  
(particularly defining a video source file with the src attribute). I  
think it all boils down to the fact that canPlayType() can return  
"maybe"; and in those cases the expected behaviour I mention isn't  
easily definable.

In our particular case, relying on Javascript isn't a deal-breaker so  
we'll go forward that way until we can see some commercial benefit  
targeting Gecko users more actively.

I do think this will mean holding out on one of the most exciting new  
features of HTML5 for the foreseeable future for client work, though  
(at least until we see what the MSIE roadmap for support looks like;  
if they require yet another new format, we'll inevitably change from a  
<video>/QT/Flash hierarchy to just QT/Flash (and lose practically  
nothing). Yet again, I think the defining factor will be the mobile  
web; if hardware decoders for OGG become cheap enough to be reasonably  
added to iPhones and Blackberries, etc. the incentive to quickly  
migrate away from Flash is more clear.

Thanks for your detailed response!

—Kit