It's just about Apple
For "non-Flash devices", simply read "Apple products".
By not supporting OGG, Firefox as well as Opera won't work, and IE9 is long from being released and won't be available for XP or 2K users, so what's the benefit of using HTML 5 here?
if you're not going to offer OGG, you still need Flash for IE, Opera, Firefox and everyone else, so what's the benefit in offering both HTML5 videos and Flash? Other than pandering to Apple's products. Why can't they just support Flash like everyone else?
The situation is crazy because if you don't want to start blocking people, you now need to offer your videos in not one but THREE FORMATS! H264, Ogg and Flash. So you may as well just offer them in Flash and let everyone use the plugin, saving yourself more than two-thirds of the disk space, transcoding time and complication.
People should stick to Flash for mainstream sites and wait for many years until IE8 is dead and gone before they start using HTML5 video tags. In the meantime, Apple can learn to get with the program and support Flash too. At the very least the dickhead politicians working at the browser companies need to stop picking 'camps' that lead all the web designers back into browser war no-mans-land, and either settle on H264 or implement support for both codecs.
Even better still, why can't Adobe and the browser companies support at least one interoperable video format so that the same file can be fed to a HTML5 tag or a flash plugin? Then they can compete on features of the players and add after effects, etc. Opera have shown after effects on HTML5 videos by using the canvas element and then using javascript (yes, javascript!) to edit the video! Flash can offer all of this using easier methods that don't require the web designer to peek and poke pixels of the video image using Javascript and a load of complicated maths.