A couple of weeks ago, I wrote about the mess regarding HTML5, Flash, and video. Some new developments have surfaced, which changes the game significantly.

Microsoft announced yesterday that Internet Explorer 9 will support only H.264 video in the HTML5 video tag.

All of the sudden, H.264 looks like it'll win the war. Microsoft doesn't traditionally pick the winning technology (if you need an example, Microsoft sided with HD-DVD years ago) but in this case, they're siding with Apple who usually does win technology wars.

To recap, HTML5 video is supported in Firefox, Opera, Chrome, and Safari. Internet Explorer has no support for HTML5 at the moment. The HTML5 video tag allows browsers to natively play video, as long as the browser knows how to support the format. There is currently a format war between the proprietary H.264 and the open source Ogg. Safari supports H.264, Firefox and Opera support Ogg, and Chrome supports both.

That means there is no "one format to rule them all."

As it stands today, you can use H.264 natively on Safari+Chrome and play that same H.264 file using a Flash player on Firefox+Opera+IE. It is a little extra work, but it is acceptable. Microsoft supporting H.264 means that you can use the same technique, but your video will play natively in Internet Explorer.

This is significant, because now the largest names in the industry are supporting a single format. Firefox and Opera will see significant pressure to adopt H.264. When that happens, Flash will become irrelevant.

The most common use of Flash right now is to deliver video. Video on the web is mess, and Flash makes it easy. But it has problems, as I outlined in my last entry. When web developers can support native video on all platforms - even iPhone OS - I guarantee they will abandon Flash as soon as possible. Developers don't enjoy using Flash to deliver video, they just do it because it is necessary.

Flash is also very popular for advertisements. But if users don't need to have Flash enabled to play video any more, how many do you think will block it? Many. And ads won't play on the iPhone at all. Do you think advertisers will keep supporting it? Not likely.

I predict Microsoft's announcement will really hurt Flash in the long run. It will put Flash back to where it around the Flash 4/5 era. Flash has its uses, it won't go away completely, but it'll certainly get knocked down a few pegs.