on Video on Web on Moving on
The article is here and from it you can pretty much understand the issue of audio and video codecs and the containers they can be delivered in. If you do not know yet what the whole flash vs html5 video debate is all about this is a must read.
The only problem with the article mentioned above is that it talks about the future.
For now here you'll find a pretty clear and to the point explanation of why flash video is here to stay for the next couple of years. That's John Harding of the YouTube API Blog.
The main reasons would be that it's been here for a while now, it works really good and it has great support.
So do we change the web because we need to change the mobile or do we leave the web as is and we figure out the optimal solution for the mobile world?
If M$ would fix IE then I think that the same efforts to support it could go in the direction of creating a mobile version for a web application.